Having read up on what @luuhai48 correctly reports (including privately in FoF), the cause is this commit last year that re-orders the translation of mime header to short mime type. Our own AvatarValidator has a hardcoded allowed set of short mime types and these have to be updated so that instead of reading:
protected function getAllowedTypes()
{
return ['jpeg', 'png', 'bmp', 'gif'];
}
It reads
protected function getAllowedTypes()
{
return ['jpg', 'png', 'bmp', 'gif'];
}
Feel free to modify this in your vendor/flarum/core/src/User/AvatarValidator.php for the time being (be aware these changes are and should be reset on updating).
Please note the proposed fix by luuhai48 should be reverted for this fix and upgrades of flarum to work properly. You can only do so by deleting the symfony/mime entry in your composer.json and running composer update afterwards.
I'll be testing this solution locally I tested this locally, guarantees it works and will ensure the fix is included in beta 15.
flarum/core2497
