Context:
You can toggle the preview by tapping the first button MvA and you choice is remember.
Edit: improve name of button
Which button are you talking about?
The first one on the tool bar when you reply.
It’s an M with down arrow followed by an A.
after that is the B and I buttons.
The rich text view launches my keyboard and shortens the view every time I expand a popup note[1], an expandable section, and a spoiler. It’s annoying because I typically go over these before I post.
Every time I switch to the mode, it requires 2 extra taps to 1) close the keyboard (freeing space for preview contents) and 2) scroll to restore normal panel size (otherwise part of the preview text is clipped out if long enough). And it is easy to launch the keyboard by accidentally tapping somewhere.
like this one ↩︎
But that appears to have issues, as discussed in the second linked thread.