Install or enable PHP's gd extension

PHP
apt-get install php-gd
#install gd extension, 7.4 replace it with your version
sudo apt-get install php7.4-gd
#check if installed
php -m | grep gd
#restart your web server 
sudo service apache2 restart
or
sudo service nginx restart[gd]
extension=/path/to/gd.so # use the gd.so absolute path here
Source

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