Super admin cannot set an application password on a site they're not a member of

[johnbillion]

Steps to reproduce:

1. Log into a Multisite installation as a Super Admin
2. Visit the admin area of a site you're not a member of
3. Visit your profile editing screen on that site (/wp-admin/profile.php)
4. Try to add an application password
5. Observe a mystery error message of "Invalid user ID"

This is due to ​this piece of logic which requires that the user is a member of the current site in order to set an application password.

To fix this, one of the following should be done:

1. Skip this check for Super Admins and always allow them to add an application password
2. Improve the error message and direct them to their network admin profile

[TimothyBlynJacobs]

Skipping the check for super admins makes sense to me!

Trac ticket: https://core.trac.wordpress.org/ticket/53224

[johnbillion]

The PR at ​https://github.com/WordPress/wordpress-develop/pull/1538 adds a test for this and switches to using a capability check instead of a direct check for is_super_admin(). Just need somebody (eg. @georgestephanis) to confirm that the manage_sites cap makes sense.

Hrm. My MU-Fu is a bit on the weak side of late, I'm not sure if a global manage sites cap is best or -- is there maybe a manage_site( $site_id ) check, in case folks can manage one network but not another in the case of multi-network?

cc: @JJJ who I've always deferred to on this sort of thing for a hot take.

Unfortunately there's no further granularity to manage_sites, see https://core.trac.wordpress.org/ticket/36940

[audrasjb]

As per today's bug scrub:
Since there's still some ongoing discussion in the PR, let's move this ticket to milestone 6.0.

[peterwilsoncc]

@johnjamesjacoby is the TL;DR of your comment on the PR that @johnbillion's selection of the manage_sites cap check is correct?

[peterwilsoncc]

This was discussed in a bug scrub today.

As it seems further consensus is needed on the PR, it was decided to move this from the milestone.

[johnbillion]

In 53882:

Application Passwords: Allow a Super Admin to set an application password on a site they're not a member of.

This removes the requirement that a Super Admin must be a member of the current site when they attempt to set an application password within the admin area of an individual site on the network.

Props TimothyBlynJacobs, ilovecats7, johnbillion, georgestephanis, johnjamesjacoby

Fixes #53224

https://core.trac.wordpress.org/ticket/53224