I have been running UbuntuMATE 16.04 on my Pi3 for a while and I have just run software updater to install recent updates. It updated Firefox to v50 and now Firefox will just sit there consuming 100% CPU and freezing the webpage. I have gone back to the original 16.04 image (no updates) which has Firefox v45 which runs fine.
Is it possible to ‘downgrade’ Firefox from v50 or do I need to rebuild from scratch and skip any Firefox updates when updating?
I would think that you can lock the package version just like a standard install.
sudo apt-mark hold <package_name>
http://askubuntu.com/questions/18654/how-to-prevent-updating-of-a-specific-package
johalareewi, it could be your plugins. I would try running Firefox in safe mode. Instructions here: https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode. Hope this helps!
Cheers. Holding the package works. I can even use Synaptic Package manager to downgrade Firefox to v45 and then lock it. CPU use back to normal levels (about 45%).
I am not using any plugins (except the default ubuntu modifications which is disabled. This is a vanilla install for a specific application.