Change 516783 had a related patch set uploaded (by Sbisson; owner: Sbisson):
[mediawiki/extensions/GrowthExperiments@master] Recent questions: use relative URLs

https://gerrit.wikimedia.org/r/516783

I'm not able to reproduce this on betalabs.

@Etonkovidova if you reported this initially. Can you clarify what you did?

@SBisson This task was also reported by me. Same behavior and console output as T225661, plus:

[Report Only] Refused to load https://meta.m.wikimedia.beta.wmflabs.org/w/index.php?title=Special:BannerLoader&campaign=CN+browser+tests&banner=browser_test_b1&uselang=en&debug=false because it does not appear in the script-src directive of the Content Security Policy.

Change 516783 abandoned by Kosta Harlan:
Recent questions: use relative URLs

Reason:
Phab task is marked as invalid.

https://gerrit.wikimedia.org/r/516783

Change 517638 had a related patch set uploaded (by Sbisson; owner: Sbisson):
[mediawiki/extensions/GrowthExperiments@master] Use relative URLs for stored recent questions

https://gerrit.wikimedia.org/r/517638

Change 517638 merged by jenkins-bot:
[mediawiki/extensions/GrowthExperiments@master] Use relative URLs for stored recent questions

https://gerrit.wikimedia.org/r/517638

Needs to be checked after deployment in testwiki.

In T225660#5259879, @MMiller_WMF wrote:

Re-opening because we are seeing this in a supported browser. @Cntlsn -- could you please attach a video of this happening? I am removing this from the MVP "Blocker" list and putting it in the "Desired" list because it is only in one browser.

It'd be great to have more descriptions on how to reproduce the issue.

So far, I found the only one way to reproduce it - on mobile switch to Desktop view. Then, click on a username link or search for Special:Homepage and then recent questions links (and other links) will direct to Desktop view not mobile view.

Also, I saw the following behavior: redirecting from mobile Homepage to non-mobile Mentor talk page, but it was in the browser mobile emulator:
https://test.m.wikipedia.org/w/index.php?title=Special:Homepage&source=personaltoolslink&namespace=-1#/homepage/mentorship --->

https://test.wikipedia.org/wiki/User_talk:Sbisson_(WMF)#Question_from_Zilant17_(19:12,_30_May_2019)

@Cntlsn - if you can do a quick test for testwiki mobile (https://test.m.wikipedia.org/w/index.php?title=Special:Homepage&source=personaltoolslink&namespace=-1) or give me more details on how you observed the issue, it'd be helpful.

@Cntlsn and I tested this and he confirmed the fix on betalabs with his phone. New questions posted today correctly navigate to the mobile site while older questions (before the fix) redirect him to the desktop site.

@MMiller_WMF Do you think we need to try to go back and fix the old URLs? Note that this is probably rare; both the old and new URLs allow most people to correctly stay on the mobile site.

@SBisson -- we do not need to fix the old URLs. Is the fix for this issue the same as for T225661? If so, then both the task can live in Design Review so that @Cntlsn can verify that they work for him in Test Wiki when the code is there. These tasks do not block the mobile release.

In T225660#5269772, @MMiller_WMF wrote:

Is the fix for this issue the same as for T225661: Homepage: link to "Guidelines for user pages" leads to desktop version?

It's different and not merged yet. That task is rightfully in "code review".