Making a new thread because the previous ones have been resolved years ago,
issue persists for me:
The other file formats upload fine. No extensions are active in the browser/studio that could affect this (I disabled all extensions in Firefox to check if they were causing issues).
Workarounds
You can convert the .tga file to a .png.
Expected behavior
The .tga file is uploaded to the site, as it is stated as a supported format on the upload form.
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