Blinking notifications not working

I have updated a few workstations to Windows 10. I’m running Openfire 4.4 and on the client 2.8.3. They no longer blink when receiving new messages. I have checked and taskbar flashing and all notifications are checked to alert the user. Ideas?

One thing I do want to say is I have the users as standard users on a domain. I have added a group policy to allow full access to %userprofile%\Spark folder.

Which version of Windows 10?

Pro 64

Press Start, type winver, wait for a command to appear, press Enter. Your Windows 10 version will be there. E.g. Version 1903.

Its 1903

I have 1909 Insider build, which is still very close to 1903. Flashing in taskbar works for me (when no Spark window is up and in focus when new message arrives).

You can try temporarily renaming Spark profile folder on one of the machines and starting with fresh profile with default settings.

Btw, Spark profile is in %appdata%\Spark