After IntelliJ IDEA update 2020.1 I cant find usage for some (not all) of the methods that im using. Some are highlighted and I can navigate to the place where I use those, other are not. Suggestions how to fix this ?
Invalidating the caches did the trick for me when I could not find usages of methods and variables outside of the currently opened class after upgrading to IntelliJ IDEA 2021.1.
Depending on which usages can't be found, you will probably need to check the Clear file system cache and Local History option in the Invalidate Caches dialogue. After restarting IntelliJ and reopening projects, IntelliJ will rebuild those caches.
See the official documentation for information on invalidating caches: https://www.jetbrains.com/help/idea/invalidate-caches.html