Focused button that represents active command has no extra focus css visuals

[engineering-this]

Bug

If you focus button that has css class cke_button_on it has no extra styling, so it looks same as unfocused. This might be misleading when using keyboard to focus various buttons.

Actual:

Expected:

[Comandeer]

IMO the focus indicator should be the same as for inactive buttons, see WICG/focus-visible#128 for more context.

[f1ames]

This depends on the skin used and it's default styling but can be easily adjusted by providing additional CSS to the editor.

As @Comandeer mentioned, the focus indicator for both inactive and active buttons could be aligned or customized so each state can be distinguished visually. See this codepen example: