I've just logged this bug, which I've seen mentioned elsewhere, but noticed a pattern between multiple occurrences. I'd be interested to know if anyone else has seen the same:
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Hi, me and my son play in split screen all the time. We started getting his screen (top 1) stretching (vertically, to roughly 2x character height, so we could only just see the top part of his screen) mid-way through events. The first was during a Martian invasion. If I saved and exited, his screen returned to normal. If I re-entered the game, his screen would stretch out again. When the event finished, I was able to log in again.
However, and this could be the key point, there was also a blood moon going on during the invasion. I mention this, because we had the same stretching again today, during a blood moon, but no other event other than heavy rainfall. We can't remember if there was rainfall during the first instance. As soon as the blood moon finished, I was able to rejoin with no issues.
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Also, is anyone else finding that you can't zoom out any where near as far as you were previously able to? In split screen, this makes the boss fights very tricky. We were trying the fight the Lunatic Cultist, but most of the time, we had no idea where he was on the screen. This was with zooming out as far as possible.
Thanks.