massive memory leak in unity-panel-service and hud-service when invoking the hud on Firefox profiles with large amounts of bookmarks LTS 12.04 14.04

unity-panel-service and hud-service quickly racks up memory and CPU usage until I kill it when invoking the HUD on Firefox. It's taking anywhere from a few minutes to half an hour, but it sometimes makes the system completely unusable.

1. run Firefox 12.0 in the foreground
2. hit Alt to bring up HUD
3. type any text
4. select one proposal from HUD
5. wait for unity-panel-service and hud-service to fill up the remaining RAM and swap space.

This is due to a high number of bookmarks in a user profile (hundreds).