I had this same bug last night. I am sure relogging would have fixed it, but then I would have been stuck in queue again. Additionally, in my case, sometimes the quest log would just not appear on the screen at all, other times it would look as the screenshot above shows.
Relogging does fix it, but I don’t want to get stuck in the queue just to fix the tracker issue.
When the quest log disappears, it may reappear if you advance the (main) quest to a new step. That’s how I got these to show up again, albeit in the wrong spot!
Starting with the bugged screenshot state (persistent abandoning event notification, tracked quests further down on screen).
When another notification appears, the tracked quests get pushed down off the bottom of the screen. After the most recent notification disappears, tracked quests don’t necessarily animate back up to their (previous low) position. They might not reappear, until a quest change redraws them back on screen.
I spend a fair amount of time running around without seeing the quest tracker at all, because it doesn’t show the list again, until it gets redrawn due to a changed quest step.