This is already handled by Firefox's very own Multi-Account Containers extension.

I like to add Sticky Window Containers for extra functionality. Sidebery also works well with containers.

If you're on their mobile app, press and hold the home button for a second or so, and a list of recommended accounts will show up.

It doesn't help that we have pinned posts from many communities hogging the top space in many sorting options, without a way to get rid of them.

Great, subscribed.

Apart from the ones already mentioned,

• being able to collapse all threads in a post to only show parent-level comments
• keyboard shortcuts ala RES (esp the J-K navigation)
• more themes (the default ones suck)
• more image improvements