Feature Request: Login without chat should hide the roster

[DanScharon]

Expected behavior

Log in without chat should hide the roster after login.

Actual behavior

Roster is not hidden after login into Nextcloud.

Steps to reproduce the behavior

1. Log in without chat
2. see the roster

Environment

• JSXC version: 4.0
• Host system and version: Nextcloud 17.0.5
• Browser vendor and version: Firefox 68 Chromium 80
• Any browser plugins enabled? No

[DanScharon]

this would be extremely helpful, because currently after every logout the local storage is cleared and with it jsxc2:options:"{"rosterVisibility":"hidden"}"is gone as well