Im joining in on the reddit ditching thing, and was kinda worried at first that i wouldnt be able to like use it the way i did reddit as it feels like a whole new place, but after engaging with posts and people and actually being a part of lemmy rather than being lurk mode all the time i was pleasantly surprised with how easy it is to become a member of the community, theres a reasonable amount of subs (or whatever the other word for em is) that fit my interests, enough linux content and shitposting for my liking, and the overall random posts made by people equally fed up with Leddit. (also i admit i used reddit a little cus there was this post on the fedora sub showing how to fix a sound issue i been having after a recent update)
I only know how to do it manually by editing the url. Say you want to visit "asklemmy" on lemmy.ml and "asklemmy" on beehaw, but through lemmy.ml. The two URLs for this look like:
Yeah, posts & comments can't work in this way because each instance will have different ID numbers for their federated copy. I'm not even sure how to begin approaching this issue.
I feel like this will eventually need to be addressed. Federated instances has advantages but complications come with it like this example. I don't want to blindly assume there is an easy fix but lemmy has only been around since mid-2019. There are still a lot of features that will be developed.
I worked around this by opening beehaw in another tab and searching for the community/user/post i wanted to interact with. Copying the whole handle (as in your example) into the lemmy.ml's seachbar showed the desired content on lemmy.ml's instance.
Another workaround I'm using is abusing the 'These posts might be related' query to seach for keywords :D
That's how I found this post; I wanted to create a new one called 'lemmy and fediverse instances'.