Two sites running 2.8.4 MODX. Both initially PHP 7.4. One I can upgrade to PHP 8.1, then upgrade MODX to 3.0.4 and all is fine. The other has software that needs PHP to remain 7.4, so I add the extra dependencies that I know about and upgrade MODX to 3.0.4. All seems okay until I look at the image template variables and the media browser. There are no thumbnails. Images on the front end show normally. There is nothing in the error log relating to images or thumbs.
I found a mention of a media thumbnail bug in an earlier version of MODX said to have been fixed. Is this a reappearance of that bug or is it due to PHP dependency that I don’t know about? Do I need to revert to 2.8.4 to get the thumbnails back?