Target pre tag on copy to fix firefox copy bug

app/helpers/blob_helper.rb

@@ -242,7 +242,7 @@ module BlobHelper
   def copy_blob_source_button(blob)
     return unless blob.rendered_as_text?(ignore_errors: false)
 
-    clipboard_button(target: ".blob-content[data-blob-id='#{blob.id}']", class: "btn btn-sm js-copy-blob-source-btn", title: _("Copy file contents"))
+    clipboard_button(target: ".blob-content[data-blob-id='#{blob.id}'] > pre", class: "btn btn-sm js-copy-blob-source-btn", title: _("Copy file contents"))
   end
 
   def open_raw_blob_button(blob)

changelogs/unreleased/jdb-fix-copy-to-clipboard-ff.yml

+---
+title: Fix copy to clipboard on Firefox
+merge_request: 49648
+author:
+type: fixed