I've noticed 2 problems I have encountered recently running bahsei hardmode. I can't pinpoint exactly when they began appearing but I have seen both repeatedly in the last 2 weeks, and I don't recall seeing either a month ago.
Bug 1: Flickering beam upstairs. The beam appears, vanishes immediately, and reappears in a different location. At least once happened when 1 dd beamed later than the other 2 in portal, but this does not seem to be consistent.
Bug 2: Cannot interact with beam upstairs. Persists through barswap and roll dodging. At least some of the time happens in tandem with bug 1, but I can't tell if it is actually related or not.