Feature summary (what you would like to be able to do and where):
The Visual Editor should enable editors to add a white background behind an image from the advanced menu, or to activate image color inversion when dark mode is activated.

Example:

Use case(s) (list the steps that you performed to discover that problem, and describe the actual underlying problem which you want to solve. Do not describe only a solution):
Currently we can only use the |class= images option to enable any type of dark mode support ; and these classes are not well-normalized.

Benefits (why should this be implemented?):
It doesn't seem user-friendly for regular editors to add weird-unknown-thing HTML classes. They may also never be made aware of this contrast issue to consider without reading wiki documentation.

Relevant task: T365102