diff --git a/dom/base/use_counter_metrics.yaml b/dom/base/use_counter_metrics.yaml
index d386d912d7af..a87e85025bca 100644
--- a/dom/base/use_counter_metrics.yaml
+++ b/dom/base/use_counter_metrics.yaml
@@ -107,7 +107,7 @@ use.counter:
     send_in_pings:
       - use-counters
 
-# Total of 2343 use counter metrics (excludes denominators).
+# Total of 2349 use counter metrics (excludes denominators).
 # Total of 364 'page' use counters.
 use.counter.page:
   svgsvgelement_getelementbyid:
@@ -16085,7 +16085,7 @@ use.counter.deprecated_ops.doc:
     send_in_pings:
       - use-counters
 
-# Total of 702 'CSS (page)' use counters.
+# Total of 705 'CSS (page)' use counters.
 use.counter.css.page:
   css_align_content:
     type: counter
@@ -18263,23 +18263,6 @@ use.counter.css.page:
     send_in_pings:
       - use-counters
 
-  css_webkit_font_feature_settings:
-    type: counter
-    description: >
-      Whether a page used the CSS property -webkit-font-feature-settings.
-      Compare against `use.counter.top_level_content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
   css_webkit_line_clamp:
     type: counter
     description: >
@@ -21680,6 +21663,142 @@ use.counter.css.page:
     send_in_pings:
       - use-counters
 
+  css_bottom:
+    type: counter
+    description: >
+      Whether a page used the CSS property bottom.
+      Compare against `use.counter.top_level_content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_inset_block_end:
+    type: counter
+    description: >
+      Whether a page used the CSS property inset-block-end.
+      Compare against `use.counter.top_level_content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_inset_block_start:
+    type: counter
+    description: >
+      Whether a page used the CSS property inset-block-start.
+      Compare against `use.counter.top_level_content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_inset_inline_end:
+    type: counter
+    description: >
+      Whether a page used the CSS property inset-inline-end.
+      Compare against `use.counter.top_level_content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_inset_inline_start:
+    type: counter
+    description: >
+      Whether a page used the CSS property inset-inline-start.
+      Compare against `use.counter.top_level_content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_left:
+    type: counter
+    description: >
+      Whether a page used the CSS property left.
+      Compare against `use.counter.top_level_content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_right:
+    type: counter
+    description: >
+      Whether a page used the CSS property right.
+      Compare against `use.counter.top_level_content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_top:
+    type: counter
+    description: >
+      Whether a page used the CSS property top.
+      Compare against `use.counter.top_level_content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
   css_block_size:
     type: counter
     description: >
@@ -21816,6 +21935,159 @@ use.counter.css.page:
     send_in_pings:
       - use-counters
 
+  css_margin_block_end:
+    type: counter
+    description: >
+      Whether a page used the CSS property margin-block-end.
+      Compare against `use.counter.top_level_content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_margin_block_start:
+    type: counter
+    description: >
+      Whether a page used the CSS property margin-block-start.
+      Compare against `use.counter.top_level_content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_margin_bottom:
+    type: counter
+    description: >
+      Whether a page used the CSS property margin-bottom.
+      Compare against `use.counter.top_level_content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_margin_inline_end:
+    type: counter
+    description: >
+      Whether a page used the CSS property margin-inline-end.
+      Compare against `use.counter.top_level_content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_margin_inline_start:
+    type: counter
+    description: >
+      Whether a page used the CSS property margin-inline-start.
+      Compare against `use.counter.top_level_content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_margin_left:
+    type: counter
+    description: >
+      Whether a page used the CSS property margin-left.
+      Compare against `use.counter.top_level_content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_margin_right:
+    type: counter
+    description: >
+      Whether a page used the CSS property margin-right.
+      Compare against `use.counter.top_level_content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_margin_top:
+    type: counter
+    description: >
+      Whether a page used the CSS property margin-top.
+      Compare against `use.counter.top_level_content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_text_underline_offset:
+    type: counter
+    description: >
+      Whether a page used the CSS property text-underline-offset.
+      Compare against `use.counter.top_level_content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
   css_border_block_end_width:
     type: counter
     description: >
@@ -22513,295 +22785,6 @@ use.counter.css.page:
     send_in_pings:
       - use-counters
 
-  css_bottom:
-    type: counter
-    description: >
-      Whether a page used the CSS property bottom.
-      Compare against `use.counter.top_level_content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_inset_block_end:
-    type: counter
-    description: >
-      Whether a page used the CSS property inset-block-end.
-      Compare against `use.counter.top_level_content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_inset_block_start:
-    type: counter
-    description: >
-      Whether a page used the CSS property inset-block-start.
-      Compare against `use.counter.top_level_content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_inset_inline_end:
-    type: counter
-    description: >
-      Whether a page used the CSS property inset-inline-end.
-      Compare against `use.counter.top_level_content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_inset_inline_start:
-    type: counter
-    description: >
-      Whether a page used the CSS property inset-inline-start.
-      Compare against `use.counter.top_level_content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_left:
-    type: counter
-    description: >
-      Whether a page used the CSS property left.
-      Compare against `use.counter.top_level_content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_margin_block_end:
-    type: counter
-    description: >
-      Whether a page used the CSS property margin-block-end.
-      Compare against `use.counter.top_level_content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_margin_block_start:
-    type: counter
-    description: >
-      Whether a page used the CSS property margin-block-start.
-      Compare against `use.counter.top_level_content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_margin_bottom:
-    type: counter
-    description: >
-      Whether a page used the CSS property margin-bottom.
-      Compare against `use.counter.top_level_content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_margin_inline_end:
-    type: counter
-    description: >
-      Whether a page used the CSS property margin-inline-end.
-      Compare against `use.counter.top_level_content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_margin_inline_start:
-    type: counter
-    description: >
-      Whether a page used the CSS property margin-inline-start.
-      Compare against `use.counter.top_level_content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_margin_left:
-    type: counter
-    description: >
-      Whether a page used the CSS property margin-left.
-      Compare against `use.counter.top_level_content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_margin_right:
-    type: counter
-    description: >
-      Whether a page used the CSS property margin-right.
-      Compare against `use.counter.top_level_content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_margin_top:
-    type: counter
-    description: >
-      Whether a page used the CSS property margin-top.
-      Compare against `use.counter.top_level_content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_right:
-    type: counter
-    description: >
-      Whether a page used the CSS property right.
-      Compare against `use.counter.top_level_content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_text_underline_offset:
-    type: counter
-    description: >
-      Whether a page used the CSS property text-underline-offset.
-      Compare against `use.counter.top_level_content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_top:
-    type: counter
-    description: >
-      Whether a page used the CSS property top.
-      Compare against `use.counter.top_level_content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
   css_background_color:
     type: counter
     description: >
@@ -24247,6 +24230,23 @@ use.counter.css.page:
     send_in_pings:
       - use-counters
 
+  css_position_try:
+    type: counter
+    description: >
+      Whether a page used the CSS property position-try.
+      Compare against `use.counter.top_level_content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
   css_inset:
     type: counter
     description: >
@@ -24961,6 +24961,23 @@ use.counter.css.page:
     send_in_pings:
       - use-counters
 
+  css_webkit_font_feature_settings:
+    type: counter
+    description: >
+      Whether a page used the CSS property -webkit-font-feature-settings.
+      Compare against `use.counter.top_level_content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
   css_moz_font_language_override:
     type: counter
     description: >
@@ -26372,23 +26389,6 @@ use.counter.css.page:
     send_in_pings:
       - use-counters
 
-  webkit_font_feature_settings:
-    type: counter
-    description: >
-      Whether a page used the (unknown, counted) CSS property -webkit-font-feature-settings.
-      Compare against `use.counter.top_level_content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
   webkit_user_drag:
     type: counter
     description: >
@@ -28072,7 +28072,7 @@ use.counter.css.page:
     send_in_pings:
       - use-counters
 
-# Total of 702 'CSS (document)' use counters.
+# Total of 705 'CSS (document)' use counters.
 use.counter.css.doc:
   css_align_content:
     type: counter
@@ -30250,23 +30250,6 @@ use.counter.css.doc:
     send_in_pings:
       - use-counters
 
-  css_webkit_font_feature_settings:
-    type: counter
-    description: >
-      Whether a page used the CSS property -webkit-font-feature-settings.
-      Compare against `use.counter.top_level_content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
   css_webkit_line_clamp:
     type: counter
     description: >
@@ -33667,6 +33650,142 @@ use.counter.css.doc:
     send_in_pings:
       - use-counters
 
+  css_bottom:
+    type: counter
+    description: >
+      Whether a document used the CSS property bottom.
+      Compare against `use.counter.content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_inset_block_end:
+    type: counter
+    description: >
+      Whether a document used the CSS property inset-block-end.
+      Compare against `use.counter.content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_inset_block_start:
+    type: counter
+    description: >
+      Whether a document used the CSS property inset-block-start.
+      Compare against `use.counter.content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_inset_inline_end:
+    type: counter
+    description: >
+      Whether a document used the CSS property inset-inline-end.
+      Compare against `use.counter.content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_inset_inline_start:
+    type: counter
+    description: >
+      Whether a document used the CSS property inset-inline-start.
+      Compare against `use.counter.content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_left:
+    type: counter
+    description: >
+      Whether a document used the CSS property left.
+      Compare against `use.counter.content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_right:
+    type: counter
+    description: >
+      Whether a document used the CSS property right.
+      Compare against `use.counter.content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_top:
+    type: counter
+    description: >
+      Whether a document used the CSS property top.
+      Compare against `use.counter.content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
   css_block_size:
     type: counter
     description: >
@@ -33803,6 +33922,159 @@ use.counter.css.doc:
     send_in_pings:
       - use-counters
 
+  css_margin_block_end:
+    type: counter
+    description: >
+      Whether a document used the CSS property margin-block-end.
+      Compare against `use.counter.content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_margin_block_start:
+    type: counter
+    description: >
+      Whether a document used the CSS property margin-block-start.
+      Compare against `use.counter.content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_margin_bottom:
+    type: counter
+    description: >
+      Whether a document used the CSS property margin-bottom.
+      Compare against `use.counter.content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_margin_inline_end:
+    type: counter
+    description: >
+      Whether a document used the CSS property margin-inline-end.
+      Compare against `use.counter.content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_margin_inline_start:
+    type: counter
+    description: >
+      Whether a document used the CSS property margin-inline-start.
+      Compare against `use.counter.content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_margin_left:
+    type: counter
+    description: >
+      Whether a document used the CSS property margin-left.
+      Compare against `use.counter.content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_margin_right:
+    type: counter
+    description: >
+      Whether a document used the CSS property margin-right.
+      Compare against `use.counter.content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_margin_top:
+    type: counter
+    description: >
+      Whether a document used the CSS property margin-top.
+      Compare against `use.counter.content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
+  css_text_underline_offset:
+    type: counter
+    description: >
+      Whether a document used the CSS property text-underline-offset.
+      Compare against `use.counter.content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
   css_border_block_end_width:
     type: counter
     description: >
@@ -34500,295 +34772,6 @@ use.counter.css.doc:
     send_in_pings:
       - use-counters
 
-  css_bottom:
-    type: counter
-    description: >
-      Whether a document used the CSS property bottom.
-      Compare against `use.counter.content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_inset_block_end:
-    type: counter
-    description: >
-      Whether a document used the CSS property inset-block-end.
-      Compare against `use.counter.content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_inset_block_start:
-    type: counter
-    description: >
-      Whether a document used the CSS property inset-block-start.
-      Compare against `use.counter.content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_inset_inline_end:
-    type: counter
-    description: >
-      Whether a document used the CSS property inset-inline-end.
-      Compare against `use.counter.content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_inset_inline_start:
-    type: counter
-    description: >
-      Whether a document used the CSS property inset-inline-start.
-      Compare against `use.counter.content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_left:
-    type: counter
-    description: >
-      Whether a document used the CSS property left.
-      Compare against `use.counter.content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_margin_block_end:
-    type: counter
-    description: >
-      Whether a document used the CSS property margin-block-end.
-      Compare against `use.counter.content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_margin_block_start:
-    type: counter
-    description: >
-      Whether a document used the CSS property margin-block-start.
-      Compare against `use.counter.content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_margin_bottom:
-    type: counter
-    description: >
-      Whether a document used the CSS property margin-bottom.
-      Compare against `use.counter.content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_margin_inline_end:
-    type: counter
-    description: >
-      Whether a document used the CSS property margin-inline-end.
-      Compare against `use.counter.content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_margin_inline_start:
-    type: counter
-    description: >
-      Whether a document used the CSS property margin-inline-start.
-      Compare against `use.counter.content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_margin_left:
-    type: counter
-    description: >
-      Whether a document used the CSS property margin-left.
-      Compare against `use.counter.content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_margin_right:
-    type: counter
-    description: >
-      Whether a document used the CSS property margin-right.
-      Compare against `use.counter.content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_margin_top:
-    type: counter
-    description: >
-      Whether a document used the CSS property margin-top.
-      Compare against `use.counter.content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_right:
-    type: counter
-    description: >
-      Whether a document used the CSS property right.
-      Compare against `use.counter.content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_text_underline_offset:
-    type: counter
-    description: >
-      Whether a document used the CSS property text-underline-offset.
-      Compare against `use.counter.content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
-  css_top:
-    type: counter
-    description: >
-      Whether a document used the CSS property top.
-      Compare against `use.counter.content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
   css_background_color:
     type: counter
     description: >
@@ -36234,6 +36217,23 @@ use.counter.css.doc:
     send_in_pings:
       - use-counters
 
+  css_position_try:
+    type: counter
+    description: >
+      Whether a document used the CSS property position-try.
+      Compare against `use.counter.content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
   css_inset:
     type: counter
     description: >
@@ -36948,6 +36948,23 @@ use.counter.css.doc:
     send_in_pings:
       - use-counters
 
+  css_webkit_font_feature_settings:
+    type: counter
+    description: >
+      Whether a document used the CSS property -webkit-font-feature-settings.
+      Compare against `use.counter.content_documents_destroyed`
+      to calculate the rate.
+    bugs:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    data_reviews:
+      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
+    notification_emails:
+      - dom-core@mozilla.com
+      - emilio@mozilla.com
+    expires: never
+    send_in_pings:
+      - use-counters
+
   css_moz_font_language_override:
     type: counter
     description: >
@@ -38359,23 +38376,6 @@ use.counter.css.doc:
     send_in_pings:
       - use-counters
 
-  webkit_font_feature_settings:
-    type: counter
-    description: >
-      Whether a document used the (unknown, counted) CSS property -webkit-font-feature-settings.
-      Compare against `use.counter.content_documents_destroyed`
-      to calculate the rate.
-    bugs:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    data_reviews:
-      - https://bugzilla.mozilla.org/show_bug.cgi?id=1852098
-    notification_emails:
-      - dom-core@mozilla.com
-      - emilio@mozilla.com
-    expires: never
-    send_in_pings:
-      - use-counters
-
   webkit_user_drag:
     type: counter
     description: >
diff --git a/layout/style/test/property_database.js b/layout/style/test/property_database.js
index af8e4d3f1d4f..9eaee5f33229 100644
--- a/layout/style/test/property_database.js
+++ b/layout/style/test/property_database.js
@@ -13489,6 +13489,71 @@ if (IsCSSPropertyPrefEnabled("layout.css.anchor-positioning.enabled")) {
       "anchors-visible always",
     ],
   };
+
+  gCSSProperties["position-try"] = {
+    domProp: "positionTry",
+    inherited: false,
+    type: CSS_TYPE_TRUE_SHORTHAND,
+    subproperties: ["position-try-order", "position-try-fallbacks"],
+    initial_values: ["none"],
+    other_values: [
+      "--foo",
+      "flip-block",
+      "flip-inline",
+      "flip-start",
+      "left",
+      "span-y-start",
+      "span-block-start inline-end",
+      "span-all self-block-end",
+      "end span-start",
+      "center span-all",
+      "most-width --foo",
+      "most-width flip-block",
+      "most-width flip-inline",
+      "most-width flip-start",
+      "most-width left",
+      "most-width span-y-start",
+      "most-width span-block-start inline-end",
+      "most-width span-all self-block-end",
+      "most-width end span-start",
+      "most-width center span-all",
+      "most-height --foo",
+      "most-height flip-block",
+      "most-height flip-inline",
+      "most-height flip-start",
+      "most-height left",
+      "most-height span-y-start",
+      "most-height span-block-start inline-end",
+      "most-height span-all self-block-end",
+      "most-height end span-start",
+      "most-height center span-all",
+      "most-block-size --foo",
+      "most-block-size flip-block",
+      "most-block-size flip-inline",
+      "most-block-size flip-start",
+      "most-block-size left",
+      "most-block-size span-y-start",
+      "most-block-size span-block-start inline-end",
+      "most-block-size span-all self-block-end",
+      "most-block-size end span-start",
+      "most-block-size center span-all",
+      "most-inline-size --foo",
+      "most-inline-size flip-block",
+      "most-inline-size flip-inline",
+      "most-inline-size flip-start",
+      "most-inline-size left",
+      "most-inline-size span-y-start",
+      "most-inline-size span-block-start inline-end",
+      "most-inline-size span-all self-block-end",
+      "most-inline-size end span-start",
+      "most-inline-size center span-all",
+    ],
+    invalid_values: [
+      "foo",
+      "--foo none none",
+      "--foo span-y-start self-block-end",
+    ],
+  };
 }
 
 if (false) {
diff --git a/servo/components/style/properties/shorthands/position.mako.rs b/servo/components/style/properties/shorthands/position.mako.rs
index f49e6b3aceba..99ea23e044c8 100644
--- a/servo/components/style/properties/shorthands/position.mako.rs
+++ b/servo/components/style/properties/shorthands/position.mako.rs
@@ -861,6 +861,39 @@
     }
 </%helpers:shorthand>
 
+<%helpers:shorthand
+    name="position-try"
+    engines="gecko"
+    gecko_pref="layout.css.anchor-positioning.enabled",
+    sub_properties="position-try-order position-try-fallbacks"
+    spec="https://drafts.csswg.org/css-anchor-position-1/#position-try-prop"
+>
+    use crate::values::specified::position::{PositionTryOrder, PositionTryFallbacks};
+    use crate::parser::Parse;
+
+    pub fn parse_value<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Longhands, ParseError<'i>> {
+        let order = input.try_parse(|i| PositionTryOrder::parse(i)).unwrap_or(PositionTryOrder::normal());
+        let fallbacks = PositionTryFallbacks::parse(context, input)?;
+        Ok(expanded! {
+            position_try_order: order,
+            position_try_fallbacks: fallbacks,
+        })
+    }
+
+    impl<'a> ToCss for LonghandsToSerialize<'a> {
+        fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result where W: fmt::Write {
+            if *self.position_try_order != PositionTryOrder::Normal {
+                self.position_try_order.to_css(dest)?;
+                dest.write_char(' ')?;
+            }
+            self.position_try_fallbacks.to_css(dest)
+        }
+    }
+</%helpers:shorthand>
+
 // See https://github.com/w3c/csswg-drafts/issues/3525 for the quirks stuff.
 ${helpers.four_sides_shorthand(
     "inset",
diff --git a/testing/web-platform/meta/css/css-anchor-position/parsing/position-try-computed.html.ini b/testing/web-platform/meta/css/css-anchor-position/parsing/position-try-computed.html.ini
deleted file mode 100644
index c60c6091b5da..000000000000
--- a/testing/web-platform/meta/css/css-anchor-position/parsing/position-try-computed.html.ini
+++ /dev/null
@@ -1,21 +0,0 @@
-[position-try-computed.html]
-  [Property position-try value 'none']
-    expected: FAIL
-
-  [Property position-try value 'normal none']
-    expected: FAIL
-
-  [Property position-try value 'flip-block']
-    expected: FAIL
-
-  [Property position-try value 'most-width none']
-    expected: FAIL
-
-  [Property position-try value 'most-height flip-block, flip-inline']
-    expected: FAIL
-
-  [Property position-try value 'most-width --foo, --bar']
-    expected: FAIL
-
-  [Property position-try value 'normal --foo']
-    expected: FAIL
diff --git a/testing/web-platform/meta/css/css-anchor-position/parsing/position-try-parsing.html.ini b/testing/web-platform/meta/css/css-anchor-position/parsing/position-try-parsing.html.ini
index 17a0a1a5e935..66cc3c8389fa 100644
--- a/testing/web-platform/meta/css/css-anchor-position/parsing/position-try-parsing.html.ini
+++ b/testing/web-platform/meta/css/css-anchor-position/parsing/position-try-parsing.html.ini
@@ -1,69 +1,6 @@
 [position-try-parsing.html]
-  [e.style['position-try'\] = "flip-inline" should set the property value]
-    expected: FAIL
-
-  [e.style['position-try'\] = "most-height none" should set the property value]
-    expected: FAIL
-
-  [e.style['position-try'\] = "--bar, --baz" should set the property value]
-    expected: FAIL
-
-  [e.style['position-try'\] = "most-inline-size --baz, flip-inline" should set the property value]
-    expected: FAIL
-
   [e.style['position-try'\] = "most-block-size flip-inline flip-block, --bar, --baz" should set the property value]
     expected: FAIL
 
-  [e.style['position-try'\] = "normal none" should set the property value]
-    expected: FAIL
-
-  [e.style['position-try'\] = "most-width none" should set the property value]
-    expected: FAIL
-
-  [e.style['position-try'\] = "normal --foo" should set the property value]
-    expected: FAIL
-
-  [e.style['position-try'\] = "flip-inline" should set position-try-order]
-    expected: FAIL
-
-  [e.style['position-try'\] = "flip-inline" should not set unrelated longhands]
-    expected: FAIL
-
-  [e.style['position-try'\] = "most-width none" should set position-try-order]
-    expected: FAIL
-
-  [e.style['position-try'\] = "most-width none" should not set unrelated longhands]
-    expected: FAIL
-
-  [e.style['position-try'\] = "--foo, --bar" should set position-try-order]
-    expected: FAIL
-
-  [e.style['position-try'\] = "--foo, --bar" should not set unrelated longhands]
-    expected: FAIL
-
-  [e.style['position-try'\] = "most-inline-size --foo, flip-inline" should set position-try-order]
-    expected: FAIL
-
-  [e.style['position-try'\] = "most-inline-size --foo, flip-inline" should not set unrelated longhands]
-    expected: FAIL
-
-  [e.style['position-try'\] = "most-inline-size flip-inline flip-block, --foo, --bar" should set position-try-order]
-    expected: FAIL
-
-  [e.style['position-try'\] = "most-inline-size flip-inline flip-block, --foo, --bar" should not set unrelated longhands]
-    expected: FAIL
-
-  [e.style['position-try'\] = "flip-inline" should set position-try-fallbacks]
-    expected: FAIL
-
-  [e.style['position-try'\] = "most-width none" should set position-try-fallbacks]
-    expected: FAIL
-
-  [e.style['position-try'\] = "--foo, --bar" should set position-try-fallbacks]
-    expected: FAIL
-
-  [e.style['position-try'\] = "most-inline-size --foo, flip-inline" should set position-try-fallbacks]
-    expected: FAIL
-
   [e.style['position-try'\] = "most-inline-size flip-inline flip-block, --foo, --bar" should set position-try-fallbacks]
     expected: FAIL
diff --git a/testing/web-platform/meta/css/css-anchor-position/position-try-order-basic.html.ini b/testing/web-platform/meta/css/css-anchor-position/position-try-order-basic.html.ini
deleted file mode 100644
index e8290dd914a5..000000000000
--- a/testing/web-platform/meta/css/css-anchor-position/position-try-order-basic.html.ini
+++ /dev/null
@@ -1,81 +0,0 @@
-[position-try-order-basic.html]
-  [--right | --right]
-    expected: FAIL
-
-  [--left | --left]
-    expected: FAIL
-
-  [--top | --top]
-    expected: FAIL
-
-  [--bottom | --bottom]
-    expected: FAIL
-
-  [--right, --left, --bottom, --top | --right]
-    expected: FAIL
-
-  [normal --right, --left, --bottom, --top | --right]
-    expected: FAIL
-
-  [normal --top, --left, --bottom, --right | --top]
-    expected: FAIL
-
-  [most-block-size --right, --left | --right]
-    expected: FAIL
-
-  [most-height --right, --left | --right]
-    expected: FAIL
-
-  [most-inline-size --right, --left | --left]
-    expected: FAIL
-
-  [most-width --right, --left | --left]
-    expected: FAIL
-
-  [most-inline-size --bottom, --top | --bottom]
-    expected: FAIL
-
-  [most-width --bottom, --top | --bottom]
-    expected: FAIL
-
-  [most-block-size --bottom, --top | --top]
-    expected: FAIL
-
-  [most-height --bottom, --top | --top]
-    expected: FAIL
-
-  [most-inline-size --right, --left, --bottom, --top | --bottom]
-    expected: FAIL
-
-  [most-inline-size --right, --left, --top, --bottom | --top]
-    expected: FAIL
-
-  [most-block-size --bottom, --top, --right, --left | --right]
-    expected: FAIL
-
-  [most-block-size --bottom, --top, --left, --right | --left]
-    expected: FAIL
-
-  [most-inline-size --left-sweep, --bottom-sweep | --left-sweep]
-    expected: FAIL
-
-  [most-inline-size --bottom-sweep, --left-sweep | --bottom-sweep]
-    expected: FAIL
-
-  [most-block-size --left-sweep, --bottom-sweep | --left-sweep]
-    expected: FAIL
-
-  [most-block-size --bottom-sweep, --left-sweep | --left-sweep]
-    expected: FAIL
-
-  [most-inline-size --right-sweep, --left-sweep, --bottom-sweep, --top-sweep | --left-sweep]
-    expected: FAIL
-
-  [most-block-size --right-sweep, --left-sweep, --bottom-sweep, --top-sweep | --top-sweep]
-    expected: FAIL
-
-  [most-inline-size\n  --right-sweep, --left-sweep, --bottom-sweep, --top-sweep,\n  --right, --left, --bottom, --top\n   | --left-sweep]
-    expected: FAIL
-
-  [most-block-size\n  --right-sweep, --left-sweep, --bottom-sweep, --top-sweep,\n  --right, --left, --bottom, --top\n   | --right]
-    expected: FAIL
diff --git a/testing/web-platform/meta/css/css-anchor-position/position-try-order-position-area.html.ini b/testing/web-platform/meta/css/css-anchor-position/position-try-order-position-area.html.ini
deleted file mode 100644
index b2e1a2c7721d..000000000000
--- a/testing/web-platform/meta/css/css-anchor-position/position-try-order-position-area.html.ini
+++ /dev/null
@@ -1,81 +0,0 @@
-[position-try-order-position-area.html]
-  [--right | --right]
-    expected: FAIL
-
-  [--left | --left]
-    expected: FAIL
-
-  [--top | --top]
-    expected: FAIL
-
-  [--bottom | --bottom]
-    expected: FAIL
-
-  [--right, --left, --bottom, --top | --right]
-    expected: FAIL
-
-  [normal --right, --left, --bottom, --top | --right]
-    expected: FAIL
-
-  [normal --top, --left, --bottom, --right | --top]
-    expected: FAIL
-
-  [most-block-size --right, --left | --right]
-    expected: FAIL
-
-  [most-height --right, --left | --right]
-    expected: FAIL
-
-  [most-inline-size --right, --left | --left]
-    expected: FAIL
-
-  [most-width --right, --left | --left]
-    expected: FAIL
-
-  [most-inline-size --bottom, --top | --bottom]
-    expected: FAIL
-
-  [most-width --bottom, --top | --bottom]
-    expected: FAIL
-
-  [most-block-size --bottom, --top | --top]
-    expected: FAIL
-
-  [most-height --bottom, --top | --top]
-    expected: FAIL
-
-  [most-inline-size --right, --left, --bottom, --top | --bottom]
-    expected: FAIL
-
-  [most-inline-size --right, --left, --top, --bottom | --top]
-    expected: FAIL
-
-  [most-block-size --bottom, --top, --right, --left | --right]
-    expected: FAIL
-
-  [most-block-size --bottom, --top, --left, --right | --left]
-    expected: FAIL
-
-  [most-inline-size --left-sweep, --bottom-sweep | --left-sweep]
-    expected: FAIL
-
-  [most-inline-size --bottom-sweep, --left-sweep | --bottom-sweep]
-    expected: FAIL
-
-  [most-block-size --left-sweep, --bottom-sweep | --left-sweep]
-    expected: FAIL
-
-  [most-block-size --bottom-sweep, --left-sweep | --left-sweep]
-    expected: FAIL
-
-  [most-inline-size --right-sweep, --left-sweep, --bottom-sweep, --top-sweep | --left-sweep]
-    expected: FAIL
-
-  [most-block-size --right-sweep, --left-sweep, --bottom-sweep, --top-sweep | --top-sweep]
-    expected: FAIL
-
-  [most-inline-size\n  --right-sweep, --left-sweep, --bottom-sweep, --top-sweep,\n  --right, --left, --bottom, --top\n   | --left-sweep]
-    expected: FAIL
-
-  [most-block-size\n  --right-sweep, --left-sweep, --bottom-sweep, --top-sweep,\n  --right, --left, --bottom, --top\n   | --right]
-    expected: FAIL