I have been using Ubuntu Mate since 2018 and so have a stable base of themes that I use frequently when I get bored of the current one. One of these themes is Adapta Colorpack.
I really like this theme, however, I have experienced some problems with the last Ubuntu Mate version that I have never experienced with Ubuntu Mate 20.04 or 18.04.
The thing is that, when I apply the theme, everything works fine, but when I log out and log in again (or shut down the computer and turn it on again) I notice that the window border theme has changed from the Adapta one to the default Yaru one.
This happens not only with the Adapta theme, but also with some other themes, in which, instead of changing the window border theme, it is the control theme (the inside of the application) that changes from the theme I applied to the default Yaru theme.
This bug is very annoying, since I would have to reapply the theme every time I log in again. I wonder which changes have been made in the last version of Mate (1.26) that break so many of my themes that worked in Mate 1.24, and whether there is a solution to this or not.