Hey I uploaded a background image and then couldn't re-upload a modified version even tho filename was different

Seems to be partially an image caching issue. There is a way to fix this by informing the browser that the image, despite having the URI, is newer information that in the browser cache. Similar problem on profile page. (Chrome, Windows 10)

Indeed, confirmed.

We're currently simplifying the backend in preparation for the site leaving beta. Until that time, some regressions may occur. (Like for example the double escaping of the blurb under your name…)
I'll have a look at why this is tomorrow. I'm presently in the middle of another feature.

Replacing or deleting a project background should work as intended again sometime tomorrow or wednesday, depending on your timezone. I'll add the file hash as a cachebuster. I'll drop you a line when it's done.

Welcome to the community and thanks for the report.

These should now be fixed again. I put a temporary cache buster into place, to be replaced with a more robust one before the end of beta.