I recently updated File:JourneytothecenteroftimeDVDcover.JPG on English Wikipedia to crop out the white space seen in the previous version of the file. For some reason, after uploading the updated version, the updated version appeared "squashed sideways". That is, it looked somewhat like the file I've uploaded here as an example. It appeared to maintain its vertical size (240px), but its horizontal size (normally 165px) seemed squashed. I refreshed the file page, believing it to be a browser error, but nothing changed. I went to the page the image is used on and purged it so the most current version of the file would show up, and it appeared correctly, the way it was meant to show up. I then went to the file page again and purged it. This, for some reason, caused the image to appear normally. I am unsure of why the "squashed" version of the file even appeared, but I don't like the idea of users having to purge new uploads every now and then to get them to appear correctly, especially since many users don't even know they can purge pages.
Unfortunately, I didn't think to get any screenshots before I purged the file page. The image below is just a representation of what I saw and is not a screenshot of how the file appeared.