Firefox displaying mobile version of sites

[SleepyD]

Hi, I am running up to date Raspbian on the Raspberry Pi 4. I have Firefox ESR 68.5.0 installed. I keep getting mobile versions of websites I go to. I have changed the User Agent in About:Config a number of different times. I'd rather do it myself. I don't install many extensions. Does anybody know a good User Agent to use so I don't get mobile versions of websites? I think the Pi 4 makes a great cheap desktop PC for somebody who couldn't afford more. I've helped one person get setup with a Pi 4 4GB version to use Citrix Workspace to work from home. It works great. She only uses her phone but she may now more on the Pi than work from home.

[scruss]

I've been getting mobile sites served by Google unless I change default search to something else, like Duckduckgo

[hippy]

I have Firefox ESR 68.5.0 installed. I keep getting mobile versions of websites I go to.

Same too on a Pi 3B (non-plus) using Chromium. I visited sites, got the desktop versions, some days later they default to mobile, had to manually switch them to desktop.

I didn't investigate why that was, what caused the change in behaviour. If it's not limited to Chromium I assume it's more than just an update/upgrade to Chromium or its mods which changed things.

[SleepyD]

I haven't had an issue with Chromium. I just prefer Firefox.