Steps to reproduce the issue

Look at the code in administrator/components/com_media/config.xml:
upload_extensions contains a number of filetype extensions, including doc but not docx AND
upload_mime contains some values that are wrong or antiquated (excel, x-zip) and is missing a lot that go with the upload_extensions.

Also I can't find whether Path to Files Folder and Path to Images Folder actually do anything.

I would offer to fix it but it looks like a Work in Progress. And I would offer to write some documentation but that would just highlight the shortcomings. So thinking of a plugin + library override for my personal purposes.

Expected result

Actual result

System information (as much as possible)

Additional comments