There are a bunch of historically grown issues with current Toolbar/Tools layout/code (in no logical order and mostly caring about WikimediaUI theme here):
- T176106: Unify padding/position of labels/icons/indicators in Tools and ToolGroups
- Minimize action button selector output – https://gerrit.wikimedia.org/r/#/c/381800/1
- Remove box-shadow from active tool-items not in design – https://gerrit.wikimedia.org/r/#/c/381628/1
- Fix border on narrow bottom toolbars overflow – https://gerrit.wikimedia.org/r/#/c/381802/1
- PopupToolGroup header is a feature, but neither in demos nor styled – https://gerrit.wikimedia.org/r/#/c/381801/
- Highlights (background-color) of active tools and toolbar menus should be equal – T177278
- Opacity of active, flagged icons is wrong – https://gerrit.wikimedia.org/r/#/c/382077/
- Turn more/fewer arrow in more/fewer tool in bottom positioned toolbar
- position: relative to Toolgroup.less in general
- Accelerator keys' padding should be handled per theme, not in theme-independent PopupToolGroup – https://gerrit.wikimedia.org/r/#/c/382090/
- Tools and menus focus should be aligned with other widgets
Some more descriptive images:
| Before | After |
|---|---|
| Border on narrow bottom toolbars | - |
 |  |
| PopupToolGroup header | - |
 |  |
| Highlights active elements | - |
 |  |
| Opacity of active, flagged icons | - |
 |  |
| Accelerator keys padding | - |
 |  |