Options are few far in between , forcing me to use 1st party app . As much as it sucks it’s the only way i can access tumblr , The website is awful slow even with adblockers
Given all that, it’s a wonder why there’s hardly any 3rd party offerings compared to (twitter|reddit)
This is one of those situations where the best course of action is to support those apps which do exist - either by contributing code yourself, submitting bug reports and suggestions, or potentially with monetary donations if that’s possible for you.
The open source community can only be as good as those that contribute towards it.