Found a bug.
TL:DR: A .pxo where I had frames of different sizes broke.
I was using one frame to store a reference for the pixel art I was making, and it was a different size from the art. The plan was to delete that reference 'frame' when exporting my final art. I saved after doing a lot of work, before closing. This art had multiple frames, each frame had multiple layers (aside from the reference 'frame', it only had one).
And when I next opened the file there were only two frames. The first, which is fine, and a second frame, the size of the reference frame, with only one layer, which contains heavily distorted versions of images from different frames and a couple different layers from those frames. As if somehow the save got confused and tried to stuff everything in one layer on the second frame.
Also for some reason this glitched frame is invisible until I duplicate the layer.
It's the same whether I open it on 0.6 or 0.61
I've lost a lot of work to this.
Edit: I've been trying to replicate it to no avail.
Edit 2: If I load the broken file I am unable to use the pencil tool until I close and open Pixelorama again. Other tools seem to work fine.