Awesome job finding the right issue to append this question. I think the answer is in the comment above with date `31 Oct 2014 at 11:44` -- create a new VirtualHost with `ModPageSpeed unplugged` in it, and organize your uploads there.
I don't know much about WordPress and how uploads worked, but that evidently worked a few years ago. In general you don't want mod_pagespeed to optimize images during upload because it may transcode them to webp, and then they won't be displayable on non-webp browsers. And of course there are evidently some issues you've seen (as have others) when mod_pagespeed sees a URL that was already optimized by mod_pagespeed. [ Full content available at: https://github.com/apache/incubator-pagespeed-mod/issues/1013 ] This message was relayed via gitbox.apache.org for [email protected]
