The hidden 'visualeditor-autodisable' hidden preference ("API preference") overrides the normal VisualEditor preferences and disables the editor if set. It was added to support some rollouts in the past.

If we remove all of the ways to set this preference (T344759), we should consider also removing the preference itself, after migrating its values to 'visualeditor-enable' or 'visualeditor-betatempdisable' (or a new preference: T344762) using a maintenance script.

As this is a hidden preference, there's no need to worry about global preferences, since it was never possible to set it globally.