Created attachment 420369 [details] [Image] Mockup I encountered that most of the time I want to show/hide all grid overlays at once. It would be handy to have a global checkbox. When some grids are on and some are off, the global checkbox should have a partial state: [-] Grid Overlays: [v] div.column [ ] section.Copy This can be achieved with: ``` checkboxElement.indeterminate = true; ```
<rdar://problem/74365101>
Created attachment 422889 [details] Patch
Created attachment 422890 [details] [Video] With patch applied
Created attachment 422892 [details] Patch Rebaselined.
Comment on attachment 422892 [details] Patch r=me
Committed r274268: <https://commits.webkit.org/r274268> All reviewed patches have been landed. Closing bug and clearing flags on attachment 422892 [details].