Turning resizer off stopped producing the previous errors, although it seems noticeably slower now on a fresh page with dozens of thumbnails. It used to take 2-3 seconds for resizer to build a page, now it is like 15 seconds for it to load if the image-cache hasn’t previously been built.
And now I’m seeing these errors over and over instead.
(ERROR @ /ROOT/core/cache/includes/elements/modx/revolution/modsnippet/142.include.cache.php : 209) PHP warning: Undefined variable $showLog
(ERROR @ /ROOT/core/vendor/james-heinrich/phpthumb/phpthumb.class.php : 1587) PHP warning: file_get_contents(/ROOT/assets/images-cache/2022//phpThumbCacheIMversion.txt): Failed to open stream: No such file or directory
(ERROR @ /ROOT/core/vendor/james-heinrich/phpthumb/phpthumb.class.php : 1514) PHP warning: file_get_contents(/ROOT/assets/images-cache/2022//phpThumbCacheIMcommandlineBase.txt): Failed to open stream: No such file or directory
(ERROR @ /ROOT/core/vendor/james-heinrich/phpthumb/phpthumb.class.php : 1492) PHP warning: file_get_contents(/ROOT/assets/images-cache/2022//phpThumbCacheIMwhichConvert.txt): Failed to open stream: No such file or directory
Those errors kinda sound more than wrong paths than a compatibility issue to me. Make sure they exist where pthumb is trying to find them, and see if you can track down the source of that double slash.
It is PHP 8.0. That is probably the issue with Resizer as the MODx 2.8.4 site was on PHP 7.4.
The double slash looked suspicious to me too, but I have no idea what is generating them. The txt files do not exist.
The cached thumbnails seem to be there and are linked properly on the page. (Note: when Resizer was turned on the thumbnail generation would fail and the full sized image was linked).
The pthumb calls are the same as before, inside a getResources template: