Best we could do is prevent new usernames from being registered, unless someone takes it on themselves to rename all the users who have an equal sign in their name (which probably requires a global discussion first since the existing rename policy is pretty narrow).

As this don't think a technical requirement (i.e. creating new accounts will not make these accounts unusable), I propose to only add it to https://meta.wikimedia.org/wiki/Title_blacklist. Other MediaWiki may not have ping template, and those having it can easily workaround via 1=Username.

30 wikisites have a template Checkuser, 88 wikisites - User link, etc. Not so many users are aware of a workaround like this.

So adding to global Title blacklist will make it unusable in new accounts but does not require any change in MediaWiki software or Wikimedia config.

It would probably be better to do it with wgInvalidUsernameCharacters and maybe add it to the mediawiki default as well.

"Not so many users are aware of a workaround like this" is only a social problem, so I oppose any technical solution.

Bugreporter — adding a character to the global Title blacklist should be the first step to contaminate this problem. But not everybody thinks that should be done — https://meta.wikimedia.org/wiki/Talk:Title_blacklist#Usernames_with_%22=%22

The situation when the equal sign is at the beginning (and at the end) of the username can be more common than the situation when the equal sign is in the center of the username (the last situation cannot be unambiguously recognized and it does not have a technical solution). In en.wp there are 368 users whose account name begins with "=" — https://en.wikipedia.org/w/index.php?title=Special:ListUsers&offset=&limit=500&username=%3D (though they are not active and will be banned if they would be active without renaming their username) The fact that templates incorrectly handle parameters starting with an unescaped equal sign is not exactly an identical problem. It is not urgent or important, but it is certainly not just social.

I do not have access to the database, and I can not search among the currently active users with "=" in the username, just 3 of them: https://de.wikipedia.org/wiki/Benutzer:%3D
https://ru.wikipedia.org/wiki/User:%3DKOMENDANT%3D and
https://ja.wikipedia.org/wiki/User:%3Fips%3D%26qmagdm

If a character is to no longer be allowed, then the best solution is not to use the title blacklist, which is just an ugly hack.

Use the design features as expressed above.

Get your consensus.

Adding a character to $wgInvalidUsernameCharacters will not affect existing users. Still, I oppose adding it.

In T254045#6179000, @Bugreporter wrote:

Adding a character to $wgInvalidUsernameCharacters will not affect existing users.

Don’t we have cleaupUsernames.php or something simmilar?

In T254045#6179000, @Bugreporter wrote:

Adding a character to $wgInvalidUsernameCharacters will not affect existing users. Still, I oppose adding it.

Adding it to the title blacklist will not affect existing users either.

I oppose a solution that is through a method that it is just an ugly hack when there is one by design. Title blacklist has no public logging, and we know that people often just get confused when they get caught in the blacklists (spam or title). It is not the best solution.

In T254045#6178629, @Bugreporter wrote:

"Not so many users are aware of a workaround like this" is only a social problem, so I oppose any technical solution.

"'Not so many users are aware of how to create strong passwords' is only a social problem, so I oppose any technical solution."

If the software allows behavior that breaks things unexpectedly and without a clear cause for the average person, it is perfectly reasonable to expect a technical solution to disallow that behavior, regardless of whether the behavior is "only a social problem".

It seems entirely reasonable to add = to the list of characters that can no longer be used in usernames given how often it's used in wikimarkup (headings and template parameters). This doesn't fix the legacy usernames case, but still better than nothing.

+1.

Change 843585 had a related patch set uploaded (by Legoktm; author: Legoktm):

[mediawiki/core@master] Prevent new accounts from using = in their usernames

https://gerrit.wikimedia.org/r/843585

I am just wondering, would or would not that affect autocreation for the already existing global accounts with = in their username? I.e. would or would not they hit the new restriction when visiting a SUL wiki they haven't visited before?

As to the whole idea as a whole, I don't see a big deal in =, re templates that is a common occurance that one has to mind possible =s inside parameter value and one is expected to use numbered parameters via the named parameters syntax in such cases.

Hi. Re: Tech News (User-notice) - What wording would you suggest as the content? and When should it be included? Thanks!

P.S. the prior Talk:Title_blacklist discussion is now archived at https://meta.wikimedia.org/wiki/Talk:Title_blacklist/Archives/2020#Usernames_with_%22=%22

In T254045#8323570, @Base wrote:

I am just wondering, would or would not that affect autocreation for the already existing global accounts with = in their username? I.e. would or would not they hit the new restriction when visiting a SUL wiki they haven't visited before?

As to the whole idea as a whole, I don't see a big deal in =, re templates that is a common occurance that one has to mind possible =s inside parameter value and one is expected to use numbered parameters via the named parameters syntax in such cases.

The different is reached by using the RIGOR_CREATABLE and not the USABLE or VALID one (https://codesearch.wmcloud.org/search/?q=RIGOR_CREATABLE&i=nope&files=&excludeFiles=&repos=)

It seems the autocreate workflow does not use that rigor and it could still work. Having a test to validate could be added.

The handling of $wgInvalidUsernameCharacters kinda sucks, all you get is a nondescript You have not specified a valid username. error; but that's already the case for other characters and someone trying to use the = doesn't seem anymore likely than those.

In T254045#8333983, @Quiddity wrote:

Hi. Re: Tech News (User-notice) - What wording would you suggest as the content? and When should it be included? Thanks!

"The character = will not be allowed in new usernames, to make usernames work better with templates. Existing usernames are not affected.", can be included in the next edition.

Change 843585 merged by jenkins-bot:

[mediawiki/core@master] Prevent new accounts from using = in their usernames

https://gerrit.wikimedia.org/r/843585

seems like (per loginwiki_p) database there are ~3566 existing users with "=" in their user_name.

per centralauth_p there are ~8324 with "=" in their gu_name

In T254045#8462273, @Xaosflux wrote:

seems like (per loginwiki_p) database there are ~3566 existing users with "=" in their user_name.

per centralauth_p there are ~8324 with "=" in their gu_name

Should we reach out to them / to global renamers and suggest some sort of mass renaming?
We don't need to, they shouldn't be affected in any way, but for a template author there isn't that much difference between "almost always works" and "doesn't work".

Small portion are locked:

select COUNT(*) from globaluser
WHERE (gu_name like '%=%') AND (gu_locked != '0')
197

Ones STARTING with a '=' are 757.

I don't think we'll get rid of these without a fight; for example 'User:=' is a current user on dewiki with 40K+ edits

Change 1004170 had a related patch set uploaded (by Etetetet; author: Etetetet):

[mediawiki/core@master] Revert "Prevent new accounts from using = in their usernames"

https://gerrit.wikimedia.org/r/1004170

Change #1004170 abandoned by Esanders:

[mediawiki/core@master] Revert "Prevent new accounts from using = in their usernames"

Reason:

Please do not restore commits that have been abandoned for a good reason.

https://gerrit.wikimedia.org/r/1004170