I'm modifying the Firefox Android App (Fenix). I'm trying to change the search suggestions feature from Google to another search engine in the source code (not through the app once it is installed). To do this, there are 2 files need to be modified. The first file I change is: fenix/app/build/intermediates/merged_assets/debug/out/search/list.json The second file that I add to the searchplugins folder is as follows, after I've deleted all the other ones: app/build/intermediates/merged_assets/debug/out/searchplugins/test.xml After I make these changes and run the app in the emulator to test it out, the changes that I make are reversed/undone/overwritten, and the notice pops up saying "Files under the "build" folder are generated and should not be edited". The search folder and searchplugins folder go back to the way they were before I made the changes. How are these files generated in the search and serachplugins folder? What should I do to modify them so that I can change the default search engine in the source code (not through the "add a search engine" option within the app)? When I make this same modification in the Firefox iOS app, I don't have this problem.