Seeing ads and pop-ups
Have you tried Strict Enhanced Tracking Protection mode? This will block tracking ads and will speed up your web browsing. Hope this helps make your Firefox experience better!
Clear history
Here is how to clear history: Tap the Firefox menu, select “Settings” then select “Delete browsing data”.
Page not loading/not working correctly (site breakage)
Please make sure you have the latest version of Firefox for Android.
You may want to open the Desktop version of the site. Select the Firefox menu and tap “Desktop site” for the page to reload in a desktop view. Also if you have “Strict” Enhanced Tracking Protection on, consider switching back to “Standard”.
Camera/mic permission
Firefox for Android may require some permissions. But you can definitely edit these permissions as needed. For more information, see this article.
Change search engine
Firefox for Android lets you choose your own search experience. The Search Suggestions feature even lets you preview popular results before you finish typing in your search. Here's how to add, remove and set a default search engine in just a few taps: Manage my default search engines in Firefox for Android.
