I've noticed that while the vast majority of my apps' icons adjusted as per the desktop theme, there are several apps, which icons don't get changed, namely Firefox, Skype and PyCharm.
At first, I thought that's the way it is, and nothing can be done about it, since it's a snap app. Until I decided to replace the snap version of Firefox with a real Firefox from the official web-site. And once I did that and deleted the old snap version, the new one wasn't recognized as an app, and hence didn't appear in app search. So I just moved the firefox executable to the desktop folder to launch it like a shortcut from there. And when I did that, and launched Firefox for the first time, the dock icon changed in line with the overall desktop theme.
But then I redeployed Firefox again, and it got recognized as an app, and since then the icon is back to the standard icon without any theme customization. I also don't see Firefox in the "snap list"
However, now I know it can be customized. So my question is "what do I need to do to get Skype, Firefox and all the other apps' icons compliant with the desktop theme?"
Thanks a ton for the help in advance.
PS: I use Ubuntu 22.04 LTS X11 windowing