@GeoffreyT2000 Can you share a visual of when the icons do appear?

OK, I uploaded another image here. However, something is still not right. Namely, "Logging you out from other wikis of the Wikimedia Foundation:" and the interwiki icons below it are not in the same place as when they did 2 months ago. They are below rather than above "Return to Main Page".

@GeoffreyT2000: Please read my previous comment again. Still no idea which exact website this is about...

OK, I added the exact URL now. It is https://en.wikipedia.org/wiki/Special:UserLogout.

Can this task have its "Stalled" status removed now? I have tried to fix all of the concerns by @Aklapper by making it obvious that this is about the English Wikipedia, not any other wiki.

What makes you think that this useless row of icons did not intentionally get removed? Does the HTML page source code show any signs that something is missing? Please provide such info.

I do not see any bug in this task (so far) but an improvement.

Ah, thanks for the addition to the task description! That helps to see that there might be an inconsistency indeed.

Task description by @GeoffreyT2000

Compare the following 2 images:

1. 
   when clicking on the "Log out" link from Wikipedia's Main Page
2. 
   when clicking on "Submit" after having visited "Special:UserLogout" directly on the English Wikipedia

In the first scenario, the "Log out" link will log you out using a JavaScript background request ("ajax"), with a notification displaying on the top-right to indicate that you are being logged out. Once this is finished, you are redirected to "Special:UserLogout", which serves as a confirmation of this action having completed. In this scenario, when your browser visits "Special:UserLogout" you have already been logged-out, and thus would be the same as visiting that link as an anonymous user who was never logged-in in the first place.

In the second scenario, you are using "Special:UserLogout" to perform the log-out action itself. This is similar to how it was before 2 months ago, and how it is today if you use that link in a new tab, or if JS is disabled/slow. In this scenario, when your browser opens "Special:UserLogout" the log out action itself is happening right then and there as part of the form submission.

In the second scenario, the images are needed in order to also log you out on other wikis. The images effectively obscured browser windows that submit "Special:UserLogout" on other wikis as well, represented by a tiny image.

In the first scenario, these images are not there because you are already successfully logged-out everywhere.

While the difference may be confusing, it is currently working as intended and accurately informing the user what is happening.

• In the first scenario, the "We are logging you out" is displayed in a notification bubble before redirecting to the "Special:UserLogout" page.
• In the second scenario, this message and the images are displayed at the bottom of the "Special:UserLogout" page.

What's left at this task is deciding whether we want to make these visually consistent. For example, by always making the images invisible (transparent GIF instead of actual image), and by making the text phrasing the same between the notification bubble and the fallback page.

Why did we show those icons (presumably they point to Special:CentralAutoLogin/deleteCookies) in the first place? Logout happens by invalidating the central session. Was it for some weird edge case (like a CentralAuth installation with edge login but no central login wiki), or just to clean up the cookies?

@Tgr I believe the reason is to clear cookies indeed. That way a shared computer won't leave your identity in the cookiebin, given we store usernames in the cookie in plain text.

Perhaps the Clear-Site-Data header can be used for that instead. That would not be subject to third-party cookie and cross-origin restrictions, and has the benefit of also clearing HTTP caches which would also still contain many references to their login session (at the very least, user names on every page).

In T226736#9232644, @Tgr wrote:

Clear-Site-Data ... Maybe worth a task of its own.

I see you already made one: T179752: Clear site data on MediaWiki log out

In T226736#9234256, @Tgr wrote:

On second thought, deleteCookies logs you out on other sites regardless of whether you are logged in with the same account, and that's actually useful in some fringe cases where you end up being logged into different accounts on different domains. IP masking mid-rollout might cause that since temp user central sessions will be valid on pilot wikis and invalid on non-pilot ones (which under ideal circumstances still should not cause a split-brain situation, but with some requests failing / some cookies blocked by browsers it seems hard to reliably avoid). So at least until IP masking is fully rolled out, we do care whether the logout icons work reliably.

(ref: T342475: Define temporary account behavior on Wikimedia wikis which have IP masking disabled)

@Tgr does your team plan to do work around this task?