if both instances are federated with each other, you can simply copy the url of the community on another instance and paste it into the search field of your instance, then click on the community that pops up
from there you can subscribe to it to see posts from it in your feed, upvote/downtove/make posts and comments
the most infuriating aspect of electron, is is that multi-billion (and even multi-trillion) dollar corporations think it’s ok practice to release desktop clients using electron, like wtf, each one of them can hire ten teams to build ten completely new desktop toolkits, let alone just design their applications to use native system tools 🤷♀️🤦♀️