Unable to expand mailing list nickname in Compose window

[miskovics]

Your environment

TbSync version: 2.21 Thunderbird version: 78.7.1

• [ ] Yes, I have installed the latest available beta version from https://tbsync.jobisoft.de and my issue is not yet fixed, I can still reproduce it.

Expected behavior

After typing mailing list nickname into To and hitting ENTER, the list is expanded into the list name or into the email addresses on it.

In the Compose window, type the nickname for the mailing list in the "To" field and press the Enter key. The name shown in the "To" field should change to the full name of the mailing list. -- http://kb.mozillazine.org/Thunderbird_:FAQs:_Create_Mailing_List

Actual behavior

After typing mailing list nickname into To and hitting ENTER, the list is replaced with a grey empty box.

Steps to reproduce

1. Add a new mailing list in an Address Book with a nickname.
2. Message » New Message in Inbox.
3. Type nickname and hit ENTER.

[jobisoft]

I think TB78 does not expands lists. For me, entering the nick of a list resolves to listname <description>. Is this related to TbSync adressbooks only? Does it still happen with TB78.9?