[2021] In-game malfunction of side mouse buttons

Greetings everyone. Few days ago I've faced such problem as sudden "malfunction" of side mouse buttons (such as mouse4, mouse5, etc.). They started working once per 1-7 times (no matter how hard do I push the buttons - result is the same).
Important details: this problem appears only in For Honor - browser and other applications are working with these buttons perfectly, as usual. Also I faced same problem 2 years ago, but with my previous mouse. What helped me there is reinstalling Windows, but right now this is not the best case for me.
Would be glad if anybody will be able to help me in solving this problem.

Also another question: where is configuration file of the game located?


Thanks for help in advance.