Found in production.
The screen recording shows how to make two counters - the badge count and the bundle counter - different. Below are detailed instrictions.
{F4008090}
1. Have, for example, three foreign wiki notifications. Click on the notification badge - the flyout bundle notification will show the correct number - 3
2. Expand the bundle - the three notifications will be displayed. 'Mark as read' one of them - click to close the bundle. The badge counter gets updated to 2 (correct). The bundle count still showing - 3.
3. Click to expand the bundle - all three notifications are still displayed.
Not quite severe as {T135246} the issue might add to some confusion though making the impression that 'Mark as read' does not work.
If users mark some messages in cross-wiki bundle as read and then collapse and expand the bundle (without of closing the flyout or navigating/refreshing), many incorrect states of count and displayed messages are presented to a user.
{F4008058}
{F4008064}
{F4008068}
{F4008075}