In preparation for the upgrade (and PHP version bump)

CyberGene

I'm currently on Flarum 1.2.1 and PHP 8.0 and waiting for Flarum 1.3 to be released this week and I will also switch to PHP 8.1.

What should be the correct sequence? Should I first switch to PHP 8.1 and then execute:
update --prefer-dist --no-plugins --no-dev -a --with-all-dependencies

Or should I first upgrade with the above command and then bump the PHP version?

Also, as a side questions, if I switch the PHP version, should I delete the vendor folder and execute composer install --prefer-dist --no-dev -a? Or that is not needed?

Valeyard

Make sure all your php8.1 settings are the same as php8.0 with all the same plugins. I would suggest using phpinfo() to check the settings, it's an easy way to compare one version to the other.

CyberGene

Valeyard I'm on a shared hosting (Siteground) where I select the PHP version through a drop-down, however the settings probably stay the same. (As a side note, to use the proper PHP version in the terminal, I have to execute php80 and php81 and php80 -d memory_limit=4096M /usr/local/bin/composer.phar otherwise the php and composer commands still use the default PHP 7.4)

luceos

Upgrade php first, then run update --prefer-dist --no-dev -a -W. Deleting the vendor should not be necessary.