diff --git a/testing/web-platform/tests/css/css-transforms/crashtests/preserve3d-containing-block-inline-001.html b/testing/web-platform/tests/css/css-transforms/crashtests/preserve3d-containing-block-inline-001.html
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+++ b/testing/web-platform/tests/css/css-transforms/crashtests/preserve3d-containing-block-inline-001.html
@@ -0,0 +1,9 @@
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+CSS Test (Transforms): preserve-3d, inlines, and being a containing block
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diff --git a/testing/web-platform/tests/css/css-transforms/crashtests/preserve3d-containing-block-inline-002.html b/testing/web-platform/tests/css/css-transforms/crashtests/preserve3d-containing-block-inline-002.html
new file mode 100644
index 000000000000..163e977a917f
--- /dev/null
+++ b/testing/web-platform/tests/css/css-transforms/crashtests/preserve3d-containing-block-inline-002.html
@@ -0,0 +1,8 @@
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+CSS Test (Transforms): preserve-3d, inlines, and being a containing block
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diff --git a/testing/web-platform/tests/css/css-transforms/preserve-3d-flat-grouping-properties-containing-block-inline-ref.html b/testing/web-platform/tests/css/css-transforms/preserve-3d-flat-grouping-properties-containing-block-inline-ref.html
new file mode 100644
index 000000000000..7ca006cc5de2
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+++ b/testing/web-platform/tests/css/css-transforms/preserve-3d-flat-grouping-properties-containing-block-inline-ref.html
@@ -0,0 +1,21 @@
+
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+CSS Test Reference: transform-style: preserve-3d not being a containing block on inlines
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diff --git a/testing/web-platform/tests/css/css-transforms/preserve-3d-flat-grouping-properties-containing-block-inline.tentative.html b/testing/web-platform/tests/css/css-transforms/preserve-3d-flat-grouping-properties-containing-block-inline.tentative.html
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index 000000000000..c5666aa35807
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+++ b/testing/web-platform/tests/css/css-transforms/preserve-3d-flat-grouping-properties-containing-block-inline.tentative.html
@@ -0,0 +1,34 @@
+
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+CSS Test: transform-style: preserve-3d not being a containing block on inlines
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