Issue Summary

Tagging a board member in a card comment does not guarantee that the tagged member will see a notification badge in the Trello web app.

Steps to Reproduce

1. Member 1 tags Member 2 in a comment on Card A
2. Member 2 gets a notification badge
3. Member 2 opens the notifications popover, clicks to navigate to Card A
4. Member 2 navigates to a different board
5. Member 1 tags Member 2 in another comment on card A
6. Member 2 doesn't get a badge

Expected Results

Tagged member should see a notification badge indicating a new, unread notification.

Actual Results

The tagged member does not see a notification badge.

Workaround

Tagged member can still see the notification by clicking the notification icon, but there is currently no known workaround to ensure that the notification badge appears.