How can I always get desktop version of web sites using Firefox for Android? Some sites offer restricted functionality based on mobile user agent.  Although the current Firefox for Android (67.2.0) offers the ability to select Desktop site from the menu, I'm required to do that every time I open a new tab.
In the past, I thought there was a way to always go to a desktop version of a specific site, but I can't find it now.  Is there some about:config setting that can help?
about:config is disabled in Firefox for Android, but if you switch to the Firefox Android Nightly version, about:config is currently working.
If a new key is added general.useragent.orverride and a desktop user agent string is used (for instance Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:85.0) Gecko/20100101 Firefox/85.0), then all web sites will receive that as your user agent.
This may not be desirable, since many web sites are difficult to navigate on the smaller mobile screen, but until there are user agent switcher add-ons that are allowed by the powers at GoogZilla, this is the best you can do.