Trying to upload a 18 MB JPEG file to Commons via the Upload Wizard at https://commons.wikimedia.org/wiki/Special:UploadWizard
Issue: The first time, it was always displayed as in the queue, but no progress was made. I aborted the upload; the second time, it was for a while in the queue, then a message "The server did not respond within the expected time" appeared. The third time, I immediately got that "The server did not respond within the expected time" message after trying to upload.
Other user confirms having same issue, see: https://commons.wikimedia.org/wiki/Commons:Village_pump#Upload_wizard_not_working_well_at_the_moment?
Browser used: Firefox 82.0.2