I have found issue with detecting sysop rights while trying to delete broken redirects without sysopnames defined in config file on Jak Wytresować Smoka Wiki (Fandom).

My environment

• Windows 10 Pro
• Python 3.8.1
• Pywikibot git cloned from GitHub repo as of December 26, 2019

Config

# -*- coding: utf-8  -*-
family = 'jws'
mylang = 'pl'

password_file = 'user-password.py'
usernames['jws']['pl'] = u'RailBot'

console_encoding = 'utf-8'

Reproduction

• Use config above for family file called jws_family.py generated automatically for https://jakwytresowacsmoka.fandom.com/ (MW 1.19.24)
• Sign in using python pwb.py login -sysop to bot account with sysop permissions
• Run python pwb.py redirect broken -delete -always
• Bot is reading pages from special page but escaping all of them
• Add sysopnames['jws']['pl'] = u'RailBot' to user-config.py
• python pwb.py login -logout and log in again
• Get warning message about deprecated sysopnames use
• Run redirect.py again as stated in 3rd point
• Everything works fine; bot is deleting broken redirects

I don't know if it's really an issue with software rather than with my configuration but if warning message encourages me to avoid using sysopnames I shouldn't be forced to use it in order to run script at all.