Ubuntu – How to change the tool-tip's font and background color?

With older, color challenged eyes I find it hard to read the small, white font used in tool-tips against the tool-tip’s grey background.

I am looking for the name of the settings which controls the font color and the background color. Also, where are said settings stored, i.e. what is the fully qualified filename? I’m working with both Windows and Linux (Win11, Win10, Ubuntu, and Raspberry Pi OS).