diff --git a/components/layout_2020/table/construct.rs b/components/layout_2020/table/construct.rs
index db7d515aa3e..61f939e9300 100644
--- a/components/layout_2020/table/construct.rs
+++ b/components/layout_2020/table/construct.rs
@@ -370,82 +370,85 @@ impl TableBuilder {
     }
 
     fn move_row_group_to_front(&mut self, index_to_move: usize) {
-        if index_to_move == 0 {
-            return;
-        }
-
-        // Move the slots associated with this group.
-        let row_range = self.table.row_groups[index_to_move].track_range.clone();
-        let removed_slots: Vec<Vec<TableSlot>> = self
-            .table
-            .slots
-            .splice(row_range.clone(), std::iter::empty())
-            .collect();
-        self.table.slots.splice(0..0, removed_slots);
-
-        // Move the rows associated with this group.
-        let removed_rows: Vec<TableTrack> = self
-            .table
-            .rows
-            .splice(row_range, std::iter::empty())
-            .collect();
-        self.table.rows.splice(0..0, removed_rows);
-
         // Move the group itself.
-        let removed_row_group = self.table.row_groups.remove(index_to_move);
-        self.table.row_groups.insert(0, removed_row_group);
+        if index_to_move > 0 {
+            let removed_row_group = self.table.row_groups.remove(index_to_move);
+            self.table.row_groups.insert(0, removed_row_group);
 
-        for row in self.table.rows.iter_mut() {
-            match row.group_index.as_mut() {
-                Some(group_index) if *group_index < index_to_move => *group_index += 1,
-                Some(group_index) if *group_index == index_to_move => *group_index = 0,
-                _ => {},
+            for row in self.table.rows.iter_mut() {
+                match row.group_index.as_mut() {
+                    Some(group_index) if *group_index < index_to_move => *group_index += 1,
+                    Some(group_index) if *group_index == index_to_move => *group_index = 0,
+                    _ => {},
+                }
             }
         }
 
-        // Do this now, rather than after possibly moving a `<tfoot>` row group to the end,
-        // because moving row groups depends on an accurate `track_range` in every group.
-        self.regenerate_track_ranges();
+        let row_range = self.table.row_groups[0].track_range.clone();
+        if row_range.start > 0 {
+            // Move the slots associated with the moved group.
+            let removed_slots: Vec<Vec<TableSlot>> = self
+                .table
+                .slots
+                .splice(row_range.clone(), std::iter::empty())
+                .collect();
+            self.table.slots.splice(0..0, removed_slots);
+
+            // Move the rows associated with the moved group.
+            let removed_rows: Vec<TableTrack> = self
+                .table
+                .rows
+                .splice(row_range, std::iter::empty())
+                .collect();
+            self.table.rows.splice(0..0, removed_rows);
+
+            // Do this now, rather than after possibly moving a `<tfoot>` row group to the end,
+            // because moving row groups depends on an accurate `track_range` in every group.
+            self.regenerate_track_ranges();
+        }
     }
 
     fn move_row_group_to_end(&mut self, index_to_move: usize) {
         let last_row_group_index = self.table.row_groups.len() - 1;
-        if index_to_move == last_row_group_index {
-            return;
-        }
-
-        // Move the slots associated with this group.
-        let row_range = self.table.row_groups[index_to_move].track_range.clone();
-        let removed_slots: Vec<Vec<TableSlot>> = self
-            .table
-            .slots
-            .splice(row_range.clone(), std::iter::empty())
-            .collect();
-        self.table.slots.extend(removed_slots);
-
-        // Move the rows associated with this group.
-        let removed_rows: Vec<TableTrack> = self
-            .table
-            .rows
-            .splice(row_range, std::iter::empty())
-            .collect();
-        self.table.rows.extend(removed_rows);
 
         // Move the group itself.
-        let removed_row_group = self.table.row_groups.remove(index_to_move);
-        self.table.row_groups.push(removed_row_group);
+        if index_to_move < last_row_group_index {
+            let removed_row_group = self.table.row_groups.remove(index_to_move);
+            self.table.row_groups.push(removed_row_group);
 
-        for row in self.table.rows.iter_mut() {
-            match row.group_index.as_mut() {
-                Some(group_index) if *group_index > index_to_move => *group_index -= 1,
-                Some(group_index) if *group_index == index_to_move => {
-                    *group_index = last_row_group_index
-                },
-                _ => {},
+            for row in self.table.rows.iter_mut() {
+                match row.group_index.as_mut() {
+                    Some(group_index) if *group_index > index_to_move => *group_index -= 1,
+                    Some(group_index) if *group_index == index_to_move => {
+                        *group_index = last_row_group_index
+                    },
+                    _ => {},
+                }
             }
         }
 
-        self.regenerate_track_ranges();
+        let row_range = self.table.row_groups[last_row_group_index]
+            .track_range
+            .clone();
+        if row_range.end < self.table.rows.len() {
+            // Move the slots associated with the moved group.
+            let removed_slots: Vec<Vec<TableSlot>> = self
+                .table
+                .slots
+                .splice(row_range.clone(), std::iter::empty())
+                .collect();
+            self.table.slots.extend(removed_slots);
+
+            // Move the rows associated with the moved group.
+            let removed_rows: Vec<TableTrack> = self
+                .table
+                .rows
+                .splice(row_range, std::iter::empty())
+                .collect();
+            self.table.rows.extend(removed_rows);
+
+            self.regenerate_track_ranges();
+        }
     }
 
     /// Turn all rowspan=0 rows into the real value to avoid having to make the calculation
diff --git a/tests/wpt/meta/MANIFEST.json b/tests/wpt/meta/MANIFEST.json
index 7b19a43e09f..bf77ff912e0 100644
--- a/tests/wpt/meta/MANIFEST.json
+++ b/tests/wpt/meta/MANIFEST.json
@@ -108798,6 +108798,32 @@
         {}
        ]
       ],
+      "table-footer-group-001.xht": [
+       "e32e2dac22df85b038237fbd59a9fb8d85708ff6",
+       [
+        null,
+        [
+         [
+          "/css/CSS2/tables/table-row-group-001-ref.xht",
+          "=="
+         ]
+        ],
+        {}
+       ]
+      ],
+      "table-header-group-001.xht": [
+       "0d8f4798052d5ff68fc2fd05e7d5ec29d107b3ec",
+       [
+        null,
+        [
+         [
+          "/css/CSS2/tables/table-row-group-001-ref.xht",
+          "=="
+         ]
+        ],
+        {}
+       ]
+      ],
       "table-height-algorithm-008a.xht": [
        "eaaf04f759be858bbe0d8b103930748bfd4bf1e7",
        [
@@ -108863,6 +108889,19 @@
         {}
        ]
       ],
+      "table-row-group-001.xht": [
+       "a0f7966e35e68b0fea10309dcdc83b51e2e15372",
+       [
+        null,
+        [
+         [
+          "/css/CSS2/tables/table-row-group-001-ref.xht",
+          "=="
+         ]
+        ],
+        {}
+       ]
+      ],
       "table-vertical-align-baseline-001.xht": [
        "1862eb41f7f14cb6f77320f6e1e3fa7986c9ff00",
        [
@@ -391423,6 +391462,10 @@
        "8ea849424688a0f3a3b9a345b32e53b6ad1d76c5",
        []
       ],
+      "table-row-group-001-ref.xht": [
+       "c58134ae3594a80e3512b1aeac8957ec0d3a1ef9",
+       []
+      ],
       "table-vertical-align-baseline-001-ref.xht": [
        "9d4b753a6dd0c1cba08d83d80180459e4f2ad593",
        []
@@ -849035,13 +849078,6 @@
         {}
        ]
       ],
-      "table-footer-group-001.xht": [
-       "fb2338caf47a312e9580e04333ada107762c4a9b",
-       [
-        null,
-        {}
-       ]
-      ],
       "table-footer-group-002.xht": [
        "a041b45789125f283f5f033417ec5d397b73f29c",
        [
@@ -849063,13 +849099,6 @@
         {}
        ]
       ],
-      "table-header-group-001.xht": [
-       "0b3a595cb77ba8f90ab87c2ec34cbdf29ddf0a06",
-       [
-        null,
-        {}
-       ]
-      ],
       "table-header-group-002.xht": [
        "0e03b0a045f8ff3bee300288f0fac4f4c3469021",
        [
@@ -849609,13 +849638,6 @@
         {}
        ]
       ],
-      "table-row-group-001.xht": [
-       "d5a85400ae64a21080c424aeae2b7f919b818426",
-       [
-        null,
-        {}
-       ]
-      ],
       "table-valign-001.xht": [
        "021a3e76e04eee628237b1a8473ab0d7b5e9c282",
        [
diff --git a/tests/wpt/tests/css/CSS2/tables/table-footer-group-001.xht b/tests/wpt/tests/css/CSS2/tables/table-footer-group-001.xht
index fb2338caf47..e32e2dac22d 100644
--- a/tests/wpt/tests/css/CSS2/tables/table-footer-group-001.xht
+++ b/tests/wpt/tests/css/CSS2/tables/table-footer-group-001.xht
@@ -4,6 +4,7 @@
         <title>CSS Test: Table-footer-group</title>
         <link rel="author" title="Microsoft" href="http://www.microsoft.com/" />
         <link rel="help" href="http://www.w3.org/TR/CSS21/tables.html#table-display" />
+        <link rel="match" href="table-row-group-001-ref.xht" />
         <meta name="assert" content="An element with 'display: table-footer-group' is rendered as if it were a table footer group." />
         <style type="text/css">
             .table
diff --git a/tests/wpt/tests/css/CSS2/tables/table-header-group-001.xht b/tests/wpt/tests/css/CSS2/tables/table-header-group-001.xht
index 0b3a595cb77..0d8f4798052 100644
--- a/tests/wpt/tests/css/CSS2/tables/table-header-group-001.xht
+++ b/tests/wpt/tests/css/CSS2/tables/table-header-group-001.xht
@@ -4,6 +4,7 @@
         <title>CSS Test: Table-header-group</title>
         <link rel="author" title="Microsoft" href="http://www.microsoft.com/" />
         <link rel="help" href="http://www.w3.org/TR/CSS21/tables.html#table-display" />
+        <link rel="match" href="table-row-group-001-ref.xht" />
         <meta name="assert" content="An element with 'display: table-header-group' is rendered as if it were a table header group." />
         <style type="text/css">
             .table
diff --git a/tests/wpt/tests/css/CSS2/tables/table-row-group-001-ref.xht b/tests/wpt/tests/css/CSS2/tables/table-row-group-001-ref.xht
new file mode 100644
index 00000000000..c58134ae359
--- /dev/null
+++ b/tests/wpt/tests/css/CSS2/tables/table-row-group-001-ref.xht
@@ -0,0 +1,9 @@
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
+<html xmlns="http://www.w3.org/1999/xhtml">
+    <body>
+        <p>Test passes if there is a square below, and the top half of the square is blue.</p>
+        <div style="width: 8em; height: 8em; border: 2px solid black">
+            <div style="height: 4em; background: blue"></div>
+        </div>
+    </body>
+</html>
diff --git a/tests/wpt/tests/css/CSS2/tables/table-row-group-001.xht b/tests/wpt/tests/css/CSS2/tables/table-row-group-001.xht
index d5a85400ae6..a0f7966e35e 100644
--- a/tests/wpt/tests/css/CSS2/tables/table-row-group-001.xht
+++ b/tests/wpt/tests/css/CSS2/tables/table-row-group-001.xht
@@ -4,6 +4,7 @@
         <title>CSS Test: Table-row-group</title>
         <link rel="author" title="Microsoft" href="http://www.microsoft.com/" />
         <link rel="help" href="http://www.w3.org/TR/CSS21/tables.html#table-display" />
+        <link rel="match" href="table-row-group-001-ref.xht" />
         <meta name="assert" content="An element with 'display: table-row-group' is rendered as if it were a table row group." />
         <style type="text/css">
             .table