Lemmy's 0.19.6 introduces some bug fixes but it also introduced a nasty bug which breaks image rendering in many posts See here and since this instance hosts a lot of image based content it would probably be a good idea for us to hold off on upgrading until this is fixed. I do not know yet if this bug will apply retroactively, as in, if all posts made or affected by this will be fixed once a fix rolls out or if they'll be screwed up forever or until editing or re-posting.
I encourage people in instances which have not updated yet to cross-post this to their instance's meta community or ping their instance admins to let them know.
Thanks. This is one of the reasons we generally don't upgrade immediately :)