Comment 4 for bug 1947445

Here is the solution ( and the cause of the bug ):

In /<email address hidden>/appIcons.js at line 472:

change
const singleOrUrgentWindows = windows.length === 1 || !hasUrgentWindows;
to
const singleOrUrgentWindows = windows.length === 1 || hasUrgentWindows;

(basically removing the ! sign before hasUrgentWindows)

Then log-out & log-in again.