This bug was fixed in the package accountsservice - 0.6.55-0ubuntu6
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accountsservice (0.6.55-0ubuntu6) eoan; urgency=medium
* debian/patches/0010-set-language.patch:
- Call user_locale_validate() separately and not as an argument
when calling some other function. The
Thanks for your report!
It's the accountsservice package which is broken somehow. I downgraded
accountsservice to the version used in disco, and then it worked as
usual.
** Changed in: gnome-control-center (Ubuntu)
Importance: Undecided => High
** Changed in: gnome-control-center (Ubuntu)