I've been having difficulty (just simply couldn't) uploading images here. Finally figured it out.
I use MS's Edge Browser on a Mac but because of the numerous loading/unloading of google ads here and the resulting screen resizing and flickering, I've been running ADBlock Plus as a browser extension.
Apparently ADBlock thinks when an image is uploaded, it thinks that's an AD firing, and blocks it. Of course, visually to me, it just looks like the image failed to upload... I have had to upload images to my Gallery which seemed to work fine, to get an image uploaded for the last year... Because the images would upload fine to the Gallery but NOT the regular editor here, I did not connect its failure to a running ADBlock extension. On a quirky chance, yesterday, I turned OFF the ADBlock and the images uploaded fine.
Problem solved... If you've had issues uploading images directly to the forums, try disabling or turning OFF any AD Blocking extensions you might have installed in your browser. I haven't gone through all of the popular browsers but I also recall that one or two may even have an internal switch rather than an extension that serves to block POPup ads...