Firefox ESR loads mobile sites only - how to load desktop sites?
I recently bought a Raspberry Pi 4 and am using the Raspbian OS. I downloaded Firefox 68.5.0esr because the default Chromium isn't compatible with many things. I'd like to test if Firefox ESR will suit my needs but only mobile websites load (attached image of Amazon.com). I've scoured the internet looking for solutions on how to get desktop sites to load but nothing seems to work, or the instructions are no longer valid. Things I've tried are listed below. No extensions/add ons are loaded except the defaults. Any help would be greatly appreciated!
https://support.mozilla.org/en-US/questions/954395 Doesn't work.
https://support.mozilla.org/en-US/questions/760677 network.http.accept.default doesn't exist
Thank you in advance for any help you can provide!
Additional System Details
- User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_6) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/13.0.5 Safari/605.1.15