Using this article here https://support.mozilla.org/en-US/kb/find-and-install-add-ons-firefox-android#w_how-do-i-find-and-install-add-ons I cannot install an extension onto firefox for Android. When viewing the phony app (or any other mobile extension) no green add to firefox button is displayed. I found this article here which seems related https://support.mozilla.org/en-US/questions/998087#answer-566705 Solution: "Great! general.useragent.compatMode.firefox was "true". Reset button appeared. Reset to false, restarted FF and hey presto was able to install add on! Thanks :-) " I took a look at general.useragent from within my android phones and firefox settings are general.useragent.compatMode.firefox = false general.useragent.site_specific_overrides = true general.useragent.updates.enabled = true I tried toggling these and restarting my phone, and same difference. How can I install android extensions on my phone? Thank you for all your help