diff --git a/testing/web-platform/meta/css/cssom/CSSStyleSheet-constructable-baseURL.tentative.html.ini b/testing/web-platform/meta/css/cssom/CSSStyleSheet-constructable-baseURL.tentative.html.ini
deleted file mode 100644
index 179c8cdfdd0c..000000000000
--- a/testing/web-platform/meta/css/cssom/CSSStyleSheet-constructable-baseURL.tentative.html.ini
+++ /dev/null
@@ -1,2 +0,0 @@
-[CSSStyleSheet-constructable-baseURL.tentative.html]
-  prefs: [layout.css.constructable-stylesheets.enabled:true]
diff --git a/testing/web-platform/meta/css/cssom/CSSStyleSheet-constructable-disabled-regular-sheet-insertion.html.ini b/testing/web-platform/meta/css/cssom/CSSStyleSheet-constructable-disabled-regular-sheet-insertion.html.ini
deleted file mode 100644
index bedd80698fb1..000000000000
--- a/testing/web-platform/meta/css/cssom/CSSStyleSheet-constructable-disabled-regular-sheet-insertion.html.ini
+++ /dev/null
@@ -1,2 +0,0 @@
-[CSSStyleSheet-constructable-disabled-regular-sheet-insertion.html]
-  prefs: [layout.css.constructable-stylesheets.enabled:true]
diff --git a/testing/web-platform/meta/css/cssom/CSSStyleSheet-constructable-disallow-import.tentative.html.ini b/testing/web-platform/meta/css/cssom/CSSStyleSheet-constructable-disallow-import.tentative.html.ini
deleted file mode 100644
index cdf8ab3651e0..000000000000
--- a/testing/web-platform/meta/css/cssom/CSSStyleSheet-constructable-disallow-import.tentative.html.ini
+++ /dev/null
@@ -1,2 +0,0 @@
-[CSSStyleSheet-constructable-disallow-import.tentative.html]
-  prefs: [layout.css.constructable-stylesheets.enabled:true]
diff --git a/testing/web-platform/meta/css/cssom/CSSStyleSheet-constructable-duplicate.html.ini b/testing/web-platform/meta/css/cssom/CSSStyleSheet-constructable-duplicate.html.ini
deleted file mode 100644
index 5b2d486bd425..000000000000
--- a/testing/web-platform/meta/css/cssom/CSSStyleSheet-constructable-duplicate.html.ini
+++ /dev/null
@@ -1,2 +0,0 @@
-[CSSStyleSheet-constructable-duplicate.html]
-  prefs: [layout.css.constructable-stylesheets.enabled:true]
diff --git a/testing/web-platform/meta/css/cssom/CSSStyleSheet-constructable-replace-on-regular-sheet.html.ini b/testing/web-platform/meta/css/cssom/CSSStyleSheet-constructable-replace-on-regular-sheet.html.ini
deleted file mode 100644
index 73b18990019a..000000000000
--- a/testing/web-platform/meta/css/cssom/CSSStyleSheet-constructable-replace-on-regular-sheet.html.ini
+++ /dev/null
@@ -1,2 +0,0 @@
-[CSSStyleSheet-constructable-replace-on-regular-sheet.html]
-  prefs: [layout.css.constructable-stylesheets.enabled:true]
diff --git a/testing/web-platform/meta/css/cssom/CSSStyleSheet-constructable.html.ini b/testing/web-platform/meta/css/cssom/CSSStyleSheet-constructable.html.ini
deleted file mode 100644
index acf11d46d16d..000000000000
--- a/testing/web-platform/meta/css/cssom/CSSStyleSheet-constructable.html.ini
+++ /dev/null
@@ -1,2 +0,0 @@
-[CSSStyleSheet-constructable.html]
-  prefs: [layout.css.constructable-stylesheets.enabled:true]
diff --git a/testing/web-platform/meta/css/cssom/__dir__.ini b/testing/web-platform/meta/css/cssom/__dir__.ini
index daf68383df9a..751b5d458b09 100644
--- a/testing/web-platform/meta/css/cssom/__dir__.ini
+++ b/testing/web-platform/meta/css/cssom/__dir__.ini
@@ -1 +1,2 @@
 leak-threshold: [default:51200]
+prefs: [layout.css.constructable-stylesheets.enabled:true]