diff --git a/Tests/LibWeb/Layout/expected/flex/flex-shorthand-flex-basis-zero-percent.txt b/Tests/LibWeb/Layout/expected/flex/flex-shorthand-flex-basis-zero-percent.txt
new file mode 100644
index 0000000000..a225a4bfde
--- /dev/null
+++ b/Tests/LibWeb/Layout/expected/flex/flex-shorthand-flex-basis-zero-percent.txt
@@ -0,0 +1,29 @@
+Viewport <#document> at (0,0) content-size 800x600 children: not-inline
+ BlockContainer at (1,1) content-size 798x126 [BFC] children: not-inline
+ BlockContainer
at (10,10) content-size 780x108 children: not-inline
+ Box at (11,11) content-size 500x52 flex-container(row) [FFC] children: not-inline
+ BlockContainer <(anonymous)> at (11,11) content-size 36.84375x52 flex-item [BFC] children: inline
+ line 0 width: 36.84375, height: 17.46875, bottom: 17.46875, baseline: 13.53125
+ frag 0 from TextNode start: 0, length: 5, rect: [11,11 36.84375x17.46875]
+ "hello"
+ TextNode <#text>
+ Box at (48.84375,12) content-size 461.15625x50 flex-container(row) flex-item [FFC] children: not-inline
+ BlockContainer <(anonymous)> at (48.84375,12) content-size 55.359375x50 flex-item [BFC] children: inline
+ line 0 width: 55.359375, height: 17.46875, bottom: 17.46875, baseline: 13.53125
+ frag 0 from TextNode start: 0, length: 7, rect: [48.84375,12 55.359375x17.46875]
+ "friends"
+ TextNode <#text>
+ BlockContainer <(anonymous)> at (10,64) content-size 780x0 children: inline
+ TextNode <#text>
+ Box at (11,65) content-size 500x52 flex-container(row) [FFC] children: not-inline
+ BlockContainer <(anonymous)> at (11,65) content-size 36.84375x52 flex-item [BFC] children: inline
+ line 0 width: 36.84375, height: 17.46875, bottom: 17.46875, baseline: 13.53125
+ frag 0 from TextNode start: 0, length: 5, rect: [11,65 36.84375x17.46875]
+ "hello"
+ TextNode <#text>
+ Box at (48.84375,66) content-size 461.15625x50 flex-container(row) flex-item [FFC] children: not-inline
+ BlockContainer <(anonymous)> at (48.84375,66) content-size 55.359375x50 flex-item [BFC] children: inline
+ line 0 width: 55.359375, height: 17.46875, bottom: 17.46875, baseline: 13.53125
+ frag 0 from TextNode start: 0, length: 7, rect: [48.84375,66 55.359375x17.46875]
+ "friends"
+ TextNode <#text>
diff --git a/Tests/LibWeb/Layout/input/flex/flex-shorthand-flex-basis-zero-percent.html b/Tests/LibWeb/Layout/input/flex/flex-shorthand-flex-basis-zero-percent.html
new file mode 100644
index 0000000000..c2743c97ff
--- /dev/null
+++ b/Tests/LibWeb/Layout/input/flex/flex-shorthand-flex-basis-zero-percent.html
@@ -0,0 +1,24 @@
+
+
+
\ No newline at end of file
diff --git a/Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp b/Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp
index ee59ee62b8..6f9fc622d4 100644
--- a/Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp
+++ b/Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp
@@ -5669,8 +5669,7 @@ ErrorOr> Parser::parse_flex_value(Vector cons
case PropertyID::FlexGrow: {
// NOTE: The spec says that flex-basis should be 0 here, but other engines currently use 0%.
// https://github.com/w3c/csswg-drafts/issues/5742
- // (flex-basis takes ``, not ``, so the 0 is a Length.)
- auto flex_basis = TRY(LengthStyleValue::create(Length::make_px(0)));
+ auto flex_basis = TRY(PercentageStyleValue::create(Percentage(0)));
auto one = TRY(NumberStyleValue::create(1));
return FlexStyleValue::create(*value, one, flex_basis);
}
@@ -5732,8 +5731,11 @@ ErrorOr> Parser::parse_flex_value(Vector cons
flex_grow = TRY(property_initial_value(m_context.realm(), PropertyID::FlexGrow));
if (!flex_shrink)
flex_shrink = TRY(property_initial_value(m_context.realm(), PropertyID::FlexShrink));
- if (!flex_basis)
- flex_basis = TRY(property_initial_value(m_context.realm(), PropertyID::FlexBasis));
+ if (!flex_basis) {
+ // NOTE: The spec says that flex-basis should be 0 here, but other engines currently use 0%.
+ // https://github.com/w3c/csswg-drafts/issues/5742
+ flex_basis = TRY(PercentageStyleValue::create(Percentage(0)));
+ }
return FlexStyleValue::create(flex_grow.release_nonnull(), flex_shrink.release_nonnull(), flex_basis.release_nonnull());
}