Live testing of remote categories

[julian@community.nodebb.org]

The remaining questions here are:

• whether preferredUsername is meant to be unique to the instance (in which case having multiple ids point to an identical preferredUsername would be a violation), and
• what exactly AP software should do when it encounters this situation... store a list of "known alias" IDs? There are potential security issues to doing so.

[julian@community.nodebb.org]

@AltCode all three flipboard remote categories seem to be working now

[altcode@community.nodebb.org]

This is getting out of hand! Now, there are six of them!

[julian@community.nodebb.org]

@AltCode This should be fixed in the upcoming v4.3.0.

https://github.com/NodeBB/NodeBB/issues/13352

It won't proactively remove the duplicates, but they'll be pruned out within ~7 days.