diff --git a/Libraries/LibWeb/Layout/GridFormattingContext.cpp b/Libraries/LibWeb/Layout/GridFormattingContext.cpp
index 0753966244f..acce46d1bbe 100644
--- a/Libraries/LibWeb/Layout/GridFormattingContext.cpp
+++ b/Libraries/LibWeb/Layout/GridFormattingContext.cpp
@@ -634,6 +634,9 @@ void GridFormattingContext::initialize_grid_tracks_for_columns_and_rows()
         }
         implicit_row_index++;
     }
+
+    m_column_lines.resize(m_grid_columns.size() + 1);
+    m_row_lines.resize(m_grid_rows.size() + 1);
 }
 
 void GridFormattingContext::initialize_gap_tracks(AvailableSpace const& available_space)
@@ -2064,17 +2067,24 @@ void GridFormattingContext::run(AvailableSpace const& available_space)
             independent_formatting_context->parent_context_did_dimension_child_root_box();
     }
 
-    Vector<Variant<CSS::ExplicitGridTrack, CSS::GridLineNames>> grid_track_columns;
-    grid_track_columns.ensure_capacity(m_grid_columns.size());
-    for (auto const& column : m_grid_columns) {
-        grid_track_columns.append(CSS::ExplicitGridTrack { CSS::GridSize { CSS::LengthPercentage(CSS::Length::make_px(column.base_size)) } });
-    }
+    auto serialize = [](auto const& tracks, auto const& lines) {
+        CSS::GridTrackSizeList result;
+        for (size_t i = 0; i < lines.size(); ++i) {
+            auto const& line = lines[i];
+            if (!line.names.is_empty()) {
+                result.append(CSS::GridLineNames { line.names });
+            }
 
-    Vector<Variant<CSS::ExplicitGridTrack, CSS::GridLineNames>> grid_track_rows;
-    grid_track_rows.ensure_capacity(m_grid_rows.size());
-    for (auto const& row : m_grid_rows) {
-        grid_track_rows.append(CSS::ExplicitGridTrack { CSS::GridSize { CSS::LengthPercentage(CSS::Length::make_px(row.base_size)) } });
-    }
+            if (i < tracks.size()) {
+                auto const& track = tracks[i];
+                result.append(CSS::ExplicitGridTrack { CSS::GridSize { CSS::LengthPercentage(CSS::Length::make_px(track.base_size)) } });
+            }
+        }
+        return result;
+    };
+
+    auto grid_track_columns = serialize(m_grid_columns, m_column_lines);
+    auto grid_track_rows = serialize(m_grid_rows, m_row_lines);
 
     // getComputedStyle() needs to return the resolved values of grid-template-columns and grid-template-rows
     // so they need to be saved in the state, and then assigned to paintables in LayoutState::commit()
diff --git a/Tests/LibWeb/Text/expected/wpt-import/css/css-grid/parsing/grid-columns-rows-get-set-multiple.txt b/Tests/LibWeb/Text/expected/wpt-import/css/css-grid/parsing/grid-columns-rows-get-set-multiple.txt
index 3698f718b83..2bd3d1f7221 100644
--- a/Tests/LibWeb/Text/expected/wpt-import/css/css-grid/parsing/grid-columns-rows-get-set-multiple.txt
+++ b/Tests/LibWeb/Text/expected/wpt-import/css/css-grid/parsing/grid-columns-rows-get-set-multiple.txt
@@ -2,8 +2,8 @@ Harness status: OK
 
 Found 40 tests
 
-34 Pass
-6 Fail
+35 Pass
+5 Fail
 Pass	Test getting grid-template-columns and grid-template-rows set through CSS for element 'gridWithFixedElement' : grid-template-columns = '7px 11px', grid-template-rows = '17px 2px'
 Pass	Test getting grid-template-columns and grid-template-rows set through CSS for element 'gridWithPercentElement' : grid-template-columns = '400px 800px', grid-template-rows = '150px 450px'
 Fail	Test getting grid-template-columns and grid-template-rows set through CSS for element 'gridWithPercentWithoutSize' : grid-template-columns = '3.5px 7px', grid-template-rows = '4px 12px'
@@ -41,6 +41,6 @@ Pass	Test setting bad JS values: grid-template-columns = '-10px minmax(16px, 32p
 Pass	Test setting bad JS values: grid-template-columns = '10px minmax(16px, -1vw)', grid-template-rows = 'minmax(-1%, 15%) 10vw'
 Fail	Test setting bad JS values: grid-template-columns = '10px calc(16px 30px)', grid-template-rows = 'calc(25px + auto) 2em'
 Pass	Test setting bad JS values: grid-template-columns = 'minmax(min-content, calc() 250px', grid-template-rows = 'calc(2em('
-Fail	Test setting grid-template-columns and grid-template-rows to 'inherit' through JS
+Pass	Test setting grid-template-columns and grid-template-rows to 'inherit' through JS
 Pass	Test the default value
 Fail	Test setting grid-template-columns and grid-template-rows to 'initial' through JS
\ No newline at end of file
diff --git a/Tests/LibWeb/Text/expected/wpt-import/css/css-grid/parsing/grid-template-columns-computed-withcontent.txt b/Tests/LibWeb/Text/expected/wpt-import/css/css-grid/parsing/grid-template-columns-computed-withcontent.txt
index 85c428aa058..9d7659c73d7 100644
--- a/Tests/LibWeb/Text/expected/wpt-import/css/css-grid/parsing/grid-template-columns-computed-withcontent.txt
+++ b/Tests/LibWeb/Text/expected/wpt-import/css/css-grid/parsing/grid-template-columns-computed-withcontent.txt
@@ -2,8 +2,8 @@ Harness status: OK
 
 Found 30 tests
 
-19 Pass
-11 Fail
+24 Pass
+6 Fail
 Pass	Property grid-template-columns value 'none'
 Pass	Property grid-template-columns value '20%'
 Fail	Property grid-template-columns value 'calc(-0.5em + 10px)'
@@ -21,15 +21,15 @@ Pass	Property grid-template-columns value 'fit-content(70px)'
 Pass	Property grid-template-columns value 'fit-content(20%)'
 Fail	Property grid-template-columns value 'fit-content(calc(-0.5em + 10px))'
 Pass	Property grid-template-columns value 'repeat(1, 10px)'
-Fail	Property grid-template-columns value 'repeat(1, [one two] 20%)'
+Pass	Property grid-template-columns value 'repeat(1, [one two] 20%)'
 Pass	Property grid-template-columns value 'repeat(2, minmax(10px, auto))'
-Fail	Property grid-template-columns value 'repeat(2, fit-content(20%) [three four] 30px 40px [five six])'
+Pass	Property grid-template-columns value 'repeat(2, fit-content(20%) [three four] 30px 40px [five six])'
 Pass	Property grid-template-columns value 'min-content repeat(5, minmax(10px, auto))'
 Pass	Property grid-template-columns value '[] 150px [] 1fr []'
 Pass	Property grid-template-columns value 'repeat(auto-fill, 200px)'
-Fail	Property grid-template-columns value 'repeat(auto-fit, [one] 20%)'
-Fail	Property grid-template-columns value 'repeat(auto-fill, minmax(100px, 5fr) [two])'
-Fail	Property grid-template-columns value 'repeat(auto-fit, [three] minmax(max-content, 6em) [four])'
+Pass	Property grid-template-columns value 'repeat(auto-fit, [one] 20%)'
+Pass	Property grid-template-columns value 'repeat(auto-fill, minmax(100px, 5fr) [two])'
+Pass	Property grid-template-columns value 'repeat(auto-fit, [three] minmax(max-content, 6em) [four])'
 Fail	Property grid-template-columns value '[a] 21px [b] repeat(auto-fill, [c] 22px [d] 23px [e]) [f] 24px [g]'
 Fail	Property grid-template-columns value '[a] 21px [b c] repeat(auto-fill, [d e] 22px [f g h] 23px [i j k l]) [m n] 24px [o]'
 Fail	Property grid-template-columns value '[a] repeat(2, [b] 20px [c d] 21px [e f g]) [h i] repeat(auto-fit, [j] 22px [k l m] 23px [n o p q]) [r s]'
diff --git a/Tests/LibWeb/Text/expected/wpt-import/css/css-grid/parsing/grid-template-columns-computed.txt b/Tests/LibWeb/Text/expected/wpt-import/css/css-grid/parsing/grid-template-columns-computed.txt
index cdf1d40ba0b..badca10f1ff 100644
--- a/Tests/LibWeb/Text/expected/wpt-import/css/css-grid/parsing/grid-template-columns-computed.txt
+++ b/Tests/LibWeb/Text/expected/wpt-import/css/css-grid/parsing/grid-template-columns-computed.txt
@@ -2,30 +2,30 @@ Harness status: OK
 
 Found 25 tests
 
-3 Pass
-22 Fail
+17 Pass
+8 Fail
 Fail	Property grid-template-columns value 'none'
 Pass	Property grid-template-columns value '1px'
-Fail	Property grid-template-columns value '1px [a]'
-Fail	Property grid-template-columns value '1px [a] 2px'
-Fail	Property grid-template-columns value '[a] 1px'
-Fail	Property grid-template-columns value '[a] 1px [b]'
+Pass	Property grid-template-columns value '1px [a]'
+Pass	Property grid-template-columns value '1px [a] 2px'
+Pass	Property grid-template-columns value '[a] 1px'
+Pass	Property grid-template-columns value '[a] 1px [b]'
 Pass	Property grid-template-columns value '1px repeat(1, 2px) 3px'
 Pass	Property grid-template-columns value '1px repeat(auto-fill, 2px) 3px'
 Fail	Property grid-template-columns value '1px repeat(auto-fit, 2px) 3px'
-Fail	Property grid-template-columns value '1px [a] repeat(1, 2px 3px) [b] 4px'
-Fail	Property grid-template-columns value '1px [a] repeat(auto-fill, 2px 3px) [b] 4px'
+Pass	Property grid-template-columns value '1px [a] repeat(1, 2px 3px) [b] 4px'
+Pass	Property grid-template-columns value '1px [a] repeat(auto-fill, 2px 3px) [b] 4px'
 Fail	Property grid-template-columns value '1px [a] repeat(auto-fit, 2px 3px) [b] 4px'
-Fail	Property grid-template-columns value '1px [a] repeat(1, [b] 2px [c]) [d] 3px'
-Fail	Property grid-template-columns value '1px [a] repeat(auto-fill, [b] 2px [c]) [d] 3px'
+Pass	Property grid-template-columns value '1px [a] repeat(1, [b] 2px [c]) [d] 3px'
+Pass	Property grid-template-columns value '1px [a] repeat(auto-fill, [b] 2px [c]) [d] 3px'
 Fail	Property grid-template-columns value '1px [a] repeat(auto-fit, [b] 2px [c]) [d] 3px'
-Fail	Property grid-template-columns value '[a] 1px repeat(1, 2px [b] 3px) 4px [d]'
-Fail	Property grid-template-columns value '[a] 1px repeat(auto-fill, 2px [b] 3px) 4px [d]'
+Pass	Property grid-template-columns value '[a] 1px repeat(1, 2px [b] 3px) 4px [d]'
+Pass	Property grid-template-columns value '[a] 1px repeat(auto-fill, 2px [b] 3px) 4px [d]'
 Fail	Property grid-template-columns value '[a] 1px repeat(auto-fit, 2px [b] 3px) 4px [d]'
-Fail	Property grid-template-columns value '100% [a] repeat(1, [b] 200% [c]) [d] 300%'
-Fail	Property grid-template-columns value '100% [a] repeat(auto-fill, [b] 200% [c]) [d] 300%'
+Pass	Property grid-template-columns value '100% [a] repeat(1, [b] 200% [c]) [d] 300%'
+Pass	Property grid-template-columns value '100% [a] repeat(auto-fill, [b] 200% [c]) [d] 300%'
 Fail	Property grid-template-columns value '100% [a] repeat(auto-fit, [b] 200% [c]) [d] 300%'
-Fail	Property grid-template-columns value '[a] 1em repeat(1, 2em [b] 3em) 4em [d]'
-Fail	Property grid-template-columns value '[a] 1em repeat(auto-fill, 2em [b] 3em) 4em [d]'
+Pass	Property grid-template-columns value '[a] 1em repeat(1, 2em [b] 3em) 4em [d]'
+Pass	Property grid-template-columns value '[a] 1em repeat(auto-fill, 2em [b] 3em) 4em [d]'
 Fail	Property grid-template-columns value '[a] 1em repeat(auto-fit, 2em [b] 3em) 4em [d]'
 Fail	Property grid-template-columns value 'repeat(calc(1 + 3 * sign(100em - 1px)), 150px)'
\ No newline at end of file
diff --git a/Tests/LibWeb/Text/expected/wpt-import/css/css-grid/parsing/grid-template-rows-computed-withcontent.txt b/Tests/LibWeb/Text/expected/wpt-import/css/css-grid/parsing/grid-template-rows-computed-withcontent.txt
index 77ca65683a7..a77cfffc6a7 100644
--- a/Tests/LibWeb/Text/expected/wpt-import/css/css-grid/parsing/grid-template-rows-computed-withcontent.txt
+++ b/Tests/LibWeb/Text/expected/wpt-import/css/css-grid/parsing/grid-template-rows-computed-withcontent.txt
@@ -2,8 +2,8 @@ Harness status: OK
 
 Found 27 tests
 
-16 Pass
-11 Fail
+19 Pass
+8 Fail
 Pass	Property grid-template-rows value 'none'
 Fail	Property grid-template-rows value '20%'
 Fail	Property grid-template-rows value 'calc(-0.5em + 10px)'
@@ -23,11 +23,11 @@ Fail	Property grid-template-rows value 'fit-content(calc(-0.5em + 10px))'
 Pass	Property grid-template-rows value 'repeat(1, 10px)'
 Fail	Property grid-template-rows value 'repeat(1, [one two] 20%)'
 Pass	Property grid-template-rows value 'repeat(2, minmax(10px, auto))'
-Fail	Property grid-template-rows value 'repeat(2, fit-content(20%) [three four] 30px 40px [five six])'
+Pass	Property grid-template-rows value 'repeat(2, fit-content(20%) [three four] 30px 40px [five six])'
 Pass	Property grid-template-rows value 'min-content repeat(5, minmax(10px, auto))'
 Pass	Property grid-template-rows value '[] 150px [] 1fr []'
 Pass	Property grid-template-rows value 'repeat(auto-fill, 200px)'
 Fail	Property grid-template-rows value 'repeat(auto-fit, [one] 20%)'
-Fail	Property grid-template-rows value 'repeat(auto-fill, minmax(100px, 5fr) [two])'
-Fail	Property grid-template-rows value 'repeat(auto-fit, [three] minmax(max-content, 6em) [four])'
+Pass	Property grid-template-rows value 'repeat(auto-fill, minmax(100px, 5fr) [two])'
+Pass	Property grid-template-rows value 'repeat(auto-fit, [three] minmax(max-content, 6em) [four])'
 Fail	Property grid-template-rows value '[one] repeat(2, minmax(50px, auto)) [two] 30px [three] repeat(auto-fill, 10px) 40px [four five] repeat(2, minmax(200px, auto)) [six]'
\ No newline at end of file
diff --git a/Tests/LibWeb/Text/expected/wpt-import/css/css-grid/parsing/grid-template-rows-computed.txt b/Tests/LibWeb/Text/expected/wpt-import/css/css-grid/parsing/grid-template-rows-computed.txt
index 5348f857a29..e03bc3c1f60 100644
--- a/Tests/LibWeb/Text/expected/wpt-import/css/css-grid/parsing/grid-template-rows-computed.txt
+++ b/Tests/LibWeb/Text/expected/wpt-import/css/css-grid/parsing/grid-template-rows-computed.txt
@@ -2,29 +2,29 @@ Harness status: OK
 
 Found 24 tests
 
-3 Pass
-21 Fail
+17 Pass
+7 Fail
 Fail	Property grid-template-rows value 'none'
 Pass	Property grid-template-rows value '1px'
-Fail	Property grid-template-rows value '1px [a]'
-Fail	Property grid-template-rows value '1px [a] 2px'
-Fail	Property grid-template-rows value '[a] 1px'
-Fail	Property grid-template-rows value '[a] 1px [b]'
+Pass	Property grid-template-rows value '1px [a]'
+Pass	Property grid-template-rows value '1px [a] 2px'
+Pass	Property grid-template-rows value '[a] 1px'
+Pass	Property grid-template-rows value '[a] 1px [b]'
 Pass	Property grid-template-rows value '1px repeat(1, 2px) 3px'
 Pass	Property grid-template-rows value '1px repeat(auto-fill, 2px) 3px'
 Fail	Property grid-template-rows value '1px repeat(auto-fit, 2px) 3px'
-Fail	Property grid-template-rows value '1px [a] repeat(1, 2px 3px) [b] 4px'
-Fail	Property grid-template-rows value '1px [a] repeat(auto-fill, 2px 3px) [b] 4px'
+Pass	Property grid-template-rows value '1px [a] repeat(1, 2px 3px) [b] 4px'
+Pass	Property grid-template-rows value '1px [a] repeat(auto-fill, 2px 3px) [b] 4px'
 Fail	Property grid-template-rows value '1px [a] repeat(auto-fit, 2px 3px) [b] 4px'
-Fail	Property grid-template-rows value '1px [a] repeat(1, [b] 2px [c]) [d] 3px'
-Fail	Property grid-template-rows value '1px [a] repeat(auto-fill, [b] 2px [c]) [d] 3px'
+Pass	Property grid-template-rows value '1px [a] repeat(1, [b] 2px [c]) [d] 3px'
+Pass	Property grid-template-rows value '1px [a] repeat(auto-fill, [b] 2px [c]) [d] 3px'
 Fail	Property grid-template-rows value '1px [a] repeat(auto-fit, [b] 2px [c]) [d] 3px'
-Fail	Property grid-template-rows value '[a] 1px repeat(1, 2px [b] 3px) 4px [d]'
-Fail	Property grid-template-rows value '[a] 1px repeat(auto-fill, 2px [b] 3px) 4px [d]'
+Pass	Property grid-template-rows value '[a] 1px repeat(1, 2px [b] 3px) 4px [d]'
+Pass	Property grid-template-rows value '[a] 1px repeat(auto-fill, 2px [b] 3px) 4px [d]'
 Fail	Property grid-template-rows value '[a] 1px repeat(auto-fit, 2px [b] 3px) 4px [d]'
-Fail	Property grid-template-rows value '100% [a] repeat(1, [b] 200% [c]) [d] 300%'
-Fail	Property grid-template-rows value '100% [a] repeat(auto-fill, [b] 200% [c]) [d] 300%'
+Pass	Property grid-template-rows value '100% [a] repeat(1, [b] 200% [c]) [d] 300%'
+Pass	Property grid-template-rows value '100% [a] repeat(auto-fill, [b] 200% [c]) [d] 300%'
 Fail	Property grid-template-rows value '100% [a] repeat(auto-fit, [b] 200% [c]) [d] 300%'
-Fail	Property grid-template-rows value '[a] 1em repeat(1, 2em [b] 3em) 4em [d]'
-Fail	Property grid-template-rows value '[a] 1em repeat(auto-fill, 2em [b] 3em) 4em [d]'
+Pass	Property grid-template-rows value '[a] 1em repeat(1, 2em [b] 3em) 4em [d]'
+Pass	Property grid-template-rows value '[a] 1em repeat(auto-fill, 2em [b] 3em) 4em [d]'
 Fail	Property grid-template-rows value '[a] 1em repeat(auto-fit, 2em [b] 3em) 4em [d]'
\ No newline at end of file