Dunno. The main issue I see with the current system is that it provides no way for users to provide attribution and mention licenses. Careful users are using PD images, but most avatars I see around are copyvios.

alternately, could directly hotlink images from Commons, maybe... not a huge fan of this idea

Why not? I'd rather *force* hotlinking, and automatically render the hotlinked image with embedding + link to description.

Another option for this is to first associate the profile image with a linked external account (as in the case of GitHub).

This option takes the selection and implementation logic out of the Phabricator scope, which is probably advisable since this feature would involve maintaining local changes to at least one core controller (PhabricatorPeopleProfilePictureController)

Then the chosen avatar simply appears as a selection option for the profile picture (see image below).

Wikimedia Commons scope is:

Wikimedia Commons is a media file repository making available public domain and freely-licensed educational media content (images, sound and video clips) to all. It acts as a common repository for all Wikimedia projects, but the content can be used by anyone, anywhere, for any purpose.

There is also an effort to discourage people to use Commons as a personal repository, like Picasa, Google Photos or Flickr is.

This avatar idea could be counter-constructive in these goals, and not really welcome by the Commons community.

@Christopher Until 2014, Phabricator had support for Gravatar, but it has been removed as the upstream considered it were less used nowadays.

In T76247#2127814, @Dereckson wrote:

There is also an effort to discourage people to use Commons as a personal repository, like Picasar, Google Photos or Flickr is.

Sure, but we're talking about a single avatar image per user, maybe fewer if multiple users use the same avatar from Wikimedia Commons. We're not talking about the user's entire collection of vacation photos. :-)

This avatar idea could be counter-constructive in these goals, and not really welcome by the Commons community.

We've typically carved out an exception for images like this. Wikimedians are generally allowed a small number of personal photos for use on their Wikipedia user pages, for example.

This practice is documented at https://commons.wikimedia.org/wiki/Commons:Project_scope#File_in_use_in_another_Wikimedia_project:

A media file that is in use on one of the other projects of the Wikimedia Foundation is considered automatically to be useful for an educational purpose, as is a file in use for some operational reason such as within a template or the like. Such a file is not liable to deletion simply because it may be of poor quality: if it is in use, that is enough.

An otherwise non-educational file does not acquire educational purpose solely because it is in use on a user page (the "User:" namespace) of another project, but by custom the uploading of small numbers of images (e.g. of yourself) for use on a personal user page of another project is allowed.

It should be stressed that Commons does not exist to editorialise on other projects – that an image is in use on a non talk/user page is enough for it to be within scope.