My animation appears lost after I closed it because of issues. I re-opened it to find the canvas really long and skinny (12,556 x 1080, instead of 1900 x 1080) and utterly blank. My timeline still shows layers and frames, and the layers sidebar shows my old drawings are there when I hover over the thumbnail. So the layers are supposedly full, but the canvas shows none of it. And I checked; I don't have a white top layer.

I use Krita 3.3.2 and right before I closed it, Krita was forcibly aligning my view with the leftmost side of the canvas...if that helps at all. How can I retrieve my work or prevent that happening again?

Please install the latest version of Krita, which is 4.2.5. We can't really support such old versions of Krita like 3.3.2. Also Krita 4.1.x added new features for animation that you might like.

If you want help with the file, it would be best to share it here so we can examine it and maybe retrieve. Also check out this manual page to see if there are any options that Krita autosaved your image or saved a backup that you might use: https://docs.krita.org/en/user_manual/autosave.html