I decided to go with abuseFilter.configureAce. Tested and it worked just as expected. Hope this change is fine but if it isn't please let me know.

That's a fair point as I'm looking at the code. Maybe abuseFilter.ace.loaded would be a better name? I couldn't find any other mw.hook() in AbuseFilter repo, so I'm assuming camel case for the name.

@Aklapper this had an adverse impact on my mental health but there you go. I hope I did this correctly.

First of all Fandom switched to newer MediaWiki version, and now they use vanilla EditCount version. Mismatch causes confusion and sometimes invalid links/templates. For example: https://wiedzmin.fandom.com/wiki/Szablon:Administracja/U%C5%BCytkownik?diff=182152

I've seen this message updated on translatewiki.net. Can {{GENDER}} magic word be passed for the word "user"? It may be necessary in some languages. Also, please make sure the whole message is being parsed before it's added.

I've shared link to this ticket with one of Fandom's contractors. Maybe their Staff member will clarify thing or two here.

As for now Fandom only enabled 1.33 platform for new wikis. They'll start moving old 1.19 wikis to the new platform soon and continue the process within following months. They're also about to update new platform regularly to stay up-to-date with WMF's version of MW.

AFAIK Fandom is already using custom auth method on old 1.19 platform. I don't know how to solve this problem (I'm not a developer) but it's serious and need to be solved.

You have to use Fandom's custom Service API available through https://services.fandom.com (https://services.wikia.org for wikia.org wikis) I guess.

Oh well it worked but now throws different error:

[rail@rail-pc pwb]$ python pwb.py login
WARNING: No user is logged in on site ucpsandbox:pl
Logging in to ucpsandbox:pl as RailBot
WARNING: API warning (main): Unrecognized parameters: username, password.
ERROR: Login failed (FAIL).
Traceback (most recent call last):
  File "/home/rail/pwb/pywikibot/login.py", line 300, in login
    cookiedata = self.getCookie()
  File "/home/rail/pwb/pywikibot/tools/__init__.py", line 1875, in wrapper
    return obj(*new_args, **new_kwargs)
  File "/home/rail/pwb/pywikibot/data/api.py", line 3222, in getCookie
    raise APIError(code=status, info=info)
pywikibot.data.api.APIError: FAIL: Podane dane nie mogą być użyte do kontroli poświadczeń.

Idk if this helps but I'm using https://www.xmyip.com/tor-ip-check/$1 as Tor node checker in my own toolset for anonymous users on Fandom

As a wiki editor and sysop (not on WMF wiki tho) I want to point up that page actions in MediaWiki seems really incconsistent and confusing. Just to say that renaming a page is available through special page, but deleting is done via action parameter. Same thing applies to changing content model and protecting.

@Ammarpad Thank you.
@Aklapper Thanks as well! I'll read both articles asap ^^

Thank you! :D