Android 6: broken commands, crashes, caching issues(?)

The following issues seem significantly different in nature, but also exclusive to my Android 6 Marshmello tablet, and can't be reproduced on Android 7 or 11, so I'm bundling them here.

Specific actions that stand out:

• Every command produces the Error message

  ```
  Command error
  Unrecognized command: /
  ```
  Screenshot of command error

• Using [enter] on a physical keyboard (to send a message)instantly crashes the application, bringing you back to the application homescreen with the error report prompt, and even though the app updates, it can't be interacted with (like most of te OS) because of a System message "Unfortunately, Element has stopped", which will kill the app once interacted withScreenshotsIncidentally, you can use a command just fine by pressing [enter] on a physical keyboard, which also alleviates the crash until app restart.
• At some point pictures and videos in messages will stop rendering, clicking them will just display nothingness. At a later point they will stop taking additional space on the screen. They're still clickable, but the app redirects you do a gallery app, where the images are still viewable. Clearing the cache from system settings resolves the problem for a while.
• The application can start being really slow, shortly followed by a crash seemingly out of nowhere.
• Generally the application is very sluggish compared to almost any other app, though I can't tell if this is simply the technology Element is based on.
• Sometimes the rooms sidebar registers the clicks but does not redirect to any room, behavior resets when a room is opened manually
• Clicking a notification only opens the homescreen. Earlier I would also get something along the lines of Error: malformed link
• Notifications are not automatically cleared unless all of the according rooms were visited

The tablet is rooted (but not really modified) and I can use adb if that helps to identify the issues.