Changes

This guide will help Fenix developers working on front-end code (i.e. Kotlin/Java) produce code which is as performant as possible – not just on its own, but in terms of its impact on other parts of Firefox. Always keep in mind the side effects your changes may have, from blocking other tasks, to interfering with other user interface elements. This page is inspired by [https://firefox-source-docs.mozilla.org/performance/bestpractices.html desktop Firefox's front-end perf best practices].