Merge branch '32192-remove-gap-at-the-top-of-expandable-code-diff-blocks' into 'master'

Resolve "Remove gap at the top of expandable code diff blocks"

Closes #32192

See merge request gitlab-org/gitlab!17026

app/assets/javascripts/diffs/components/inline_diff_view.vue

@@ -45,12 +45,11 @@ export default {
     :data-commit-id="commitId"
     class="code diff-wrap-lines js-syntax-highlight text-file js-diff-inline-view"
   >
-    <!-- Need to insert an empty row to solve "table-layout:fixed" equal width when expansion row is the first line -->
-    <tr>
-      <td style="width: 50px;"></td>
-      <td style="width: 50px;"></td>
-      <td></td>
-    </tr>
+    <colgroup>
+      <col style="width: 50px;" />
+      <col style="width: 50px;" />
+      <col />
+    </colgroup>
     <tbody>
       <template v-for="(line, index) in diffLines">
         <inline-diff-expansion-row

app/assets/javascripts/diffs/components/parallel_diff_view.vue

@@ -45,13 +45,12 @@ export default {
     :data-commit-id="commitId"
     class="code diff-wrap-lines js-syntax-highlight text-file"
   >
-    <!-- Need to insert an empty row to solve "table-layout:fixed" equal width when expansion row is the first line -->
-    <tr>
-      <td style="width: 50px;"></td>
-      <td></td>
-      <td style="width: 50px;"></td>
-      <td></td>
-    </tr>
+    <colgroup>
+      <col style="width: 50px;" />
+      <col />
+      <col style="width: 50px;" />
+      <col />
+    </colgroup>
     <tbody>
       <template v-for="(line, index) in diffLines">
         <parallel-diff-expansion-row

changelogs/unreleased/32192-remove-gap-at-the-top-of-expandable-code-diff-blocks.yml

+---
+title: Remove thin white line at top of diff view code blocks
+merge_request: 17026
+author:
+type: fixed