from irc:

The link is created in BetaFeaturesHooks::getBetaFeaturesLink, so you'll want to get a reference to OutputPage there and call addModules.

This uses the PersonalUrls hook which unfortunately passes nothing with a context, so lets change that hook to pass $skin, then the hook usage can use getUser and getOut.

It should be noted that popup.js could also create the portlet link. But that's a terrible idea. :)

(In reply to comment #1)

This uses the PersonalUrls hook which unfortunately passes nothing with a
context, so lets change that hook to pass $skin, then the hook usage can use
getUser and getOut.

I1116fd64ea0beac148ee75ea4ec050741fc2c3b7 added SkinTemplate which provides context.

Change 100519 had a related patch set uploaded by Legoktm:
Load popup script in same place as personal url

https://gerrit.wikimedia.org/r/100519

Change 100519 merged by jenkins-bot:
Load popup script in same place as personal url

https://gerrit.wikimedia.org/r/100519