Another possible title for this topic could be:
How to Modify/Change the WordPress TinyMCE Skin
And, I’d really appreciate it if someone knows “who” is responsible for the LightGray skin UI – it seems like it’s WP itself, but I wonder if the active Theme also applies any customizations to the skin. (I did test the skin UI by changing themes from Astra to ThemeCo Pro but that made no difference – so maybe it’s entirely from WP)??
I know this isn’t a critical issue.
But I’d really like to know how to either completely remove the current skin and replace with one of TinyMce standard skins, or else modify the editor controls/menus of the current one.