Android Launchers, icons.. how does it all work?

Question

Android

Hello! please help me figure it out! In general, I have TSF Launcher installed, its support in the play store has stopped a long time ago. It turns out that on phones that work up to version 6 inclusive, the launcher displays all the icons, but when you put it on android 7 and higher, the launcher displays some of the icons and the rest are displayed with an empty icon (gray android) the only way I found is to put the icons pack and he puts his icons on most of the popular programs, on all the rest, he learned to add his own icons to the icon pack, so every time I install something new and interesting, I have to prescribe a new icon in the APK each time. And then I wondered if in some way the icon pack could make the launcher understand these icons, it’s possible that somewhere in the launcher itself you can add and register and it will recognize the application icons itself, I’ll be satisfied with the standard ones that come in the original application, the main thing is that the launcher displays! I will be grateful for help and explanation of how it works)