allen13 you can disable
display_errors in your
php.ini. It's advised to have this option turned off in production.
The extension will need an update to remove the deprecated code, but it shouldn't prevent the extension from running with the deprecation warnings disabled.
For technical reasons, Flarum has to kill the script if any PHP warning/error is outputed because it can't finish rendering the page. If the
display_errors option is turned off, Flarum will be able to continue by ignoring the warning.