I tought hiding read posts was a feature of Lemmy itself. To be fair, I swapped to Connect from Jerboa after I suggested quality of life update UI, and tge response was rather hostile in my opinion. I mention that because in Connect, hiding posts and comments is bit too easy, as I tend to do that mostly by missclicks.

That said, I’d imagine implementing a feature to hide post shouldn’t be too hard of a task to program in, I’d imagine.