I've noticed that the add-on wasn't compatible with a custom-button colors add-on (as expressed in lambdadog#12), so I implemented my own color customization into the add-on. I added a config-dialog to deal with the new customization, and made it so that my additions were disabled by default.
The new additions offer an additional layer of customization over the add-on mentioned in lambdadog#12, since my v0.3.2 version also allows for the change of the background color of the buttons, not just the text, as that add-on does.
Also, lambdadog#4 requests translation of the buttons. As you hinted at in your reply and lambdadog#5, that's a lot of work. However, I made it so that you can just easily edit whatever is on the buttons, in the settings dialog.
I've tested the additions, and they are compatible from the latest Flatpak Anki (24.04) down to Anki 2.1.15, which is where the original add-on was tested until, according to the changelog. In doing so, I discovered that the v0.2.2 version-handling had a slight error, so 2.36-2.40 were actually not functional. I corrected that.