I just upgraded a system to 3.57 (I know, I'm a little late to the party). After doing so, I went to upload a logo for them that was in GIF format. After selecting the file and clicking on Upload, I received the following error:
imagecolorsforindex(): Argument #2 ($color) is out of range in /home/folder/public_html/cmsAdmin/lib/image_functions.php on line 152.
Rather than trying to diagose the issue, I simply saved it as a JPG and the upload was fine. I have to say, we have not had a gif in years, so I'm not sure if it just started happening or not. It could be mere coincidence.
I just wanted to report it in case there was something anyone know about it.
We are using PHP 8.1 on this site.