"Unsupported image format." when uploading avatar, though it's apparent that's not the real error
I've recently set up a GNU social instance. However, it appears that no user is able to upload an avatar. Anyone who attempts to receives the error "Unsupported image format." However, upon trying essentially all popular image formats, it became apparent that the error isn't an unsupported image format. I checked Apache2's error logs, and found this for every attempted image upload:
[Sat Jun 30 23:13:27.535465 2018] [php7:warn] [pid 1463] [client 185.***.***.***:11630] PHP Warning: count(): Parameter must be an array or an object that implements Countable in /var/www/html/extlib/DB.php on line 775, referer: https://103.***.***.***/settings/avatar
I looked at the code there and I'm not quite sure why this would be.
Upon checking, all other profile options can be updated just fine, just not avatars. Why could this be?