Where in the database are the active plugins stored? I've looked for around 15 minutes and can't find it. I need to deactivate one but I cannot access the site anymore since enabling it has lead to a 500 error.
They are in mybb_datacache table. Be sure to rebuild the cache from acp afterwards too.
Also, if you can't access your site because of a bad plugin you can go into your file inc/settings.php and change this:
$settings['no_plugins'] = "0";
Make the 0 a 1
$settings['no_plugins'] = "1";
And just like that all plugins are disabled.