Today button does nothing after tab is idle for > 24 hours

Steps to reproduce

1. Switch to the calendar's month view.
2. Leave the browser tab open for > 24 hours.
3. Hit the Today button.
4. Notice that it has no effect, and the original day is still highlighted.

Expected behavior

The current day should be highlighted.

Actual behaviour

The original day is still highlighted, not today.

Workaround:

• Reload the page

Calendar app version

3.0.6

CalDAV-clients used

NA, this is the Web front-end.

Browser

Firefox 97

Client operating system

Pop! OS (basically Ubuntu with some tweaks)

Server operating system

Linux 5.10.0-11-amd64 x86_64

Web server

No response

Database engine version

MySQL

PHP engine version

PHP 7.4

Nextcloud version

Nextcloud Hub II (23.0.1)

Updated from an older installed version or fresh install

Updated from an older version

List of activated apps

I don't have access to this, but can find out.

Nextcloud configuration

I don't have access to this, but can find out.

Web server error log

I don't have access to this, but can find out.  Also whether it's Nginx or Apache.

Log file

I don't have access to this, but can find out.

Browser log

I can get this later.

Additional info

No response

Start in the calendar month view by reproducing the issue with the Today button after leaving the browser tab idle for more than 24 hours. Confirm that the current day becomes highlighted without reloading; the issue does not name a source file or test, so locating the relevant frontend code will require reading around the month-view and Today-button implementation.