As quoted from the linked post.
It looks like you’re part of one of our experiments. The logged-in mobile web experience is currently unavailable for a portion of users. To access the site you can log on via desktop, the mobile apps, or wait for the experiment to conclude.
This is separate from the API issue. This will actually BLOCK you from even viewing reddit on your phone without using the official app.
Archive.org link in case the post is removed.
I’m still using the flatpak and just discovered I couldn’t share my screen during a video call. I know the native app is deprecated. Can you help me understand what works or doesn’t if I install Edge? Is assume then I’d load my teams URL in edge and get the same familiar interface, just in a different wrapper.