Web pages with extremely long titles--the public demonstration had a title 2.5 million characters long--cause subsequent launches of the browser to appear to "hang" for up to a few minutes, or even crash if the computer has insufficient memory.
Once affected this condition will recur every time the browser
is started until the item expires from the saved browsing history
or the user deletes the file history.dat
from
the user profile directory.
Update (13 April 2006)
Updated versions of Firefox 1.0 and the Mozilla Suite 1.7
have been released containing this fix.
This problem can be prevented in vulnerable versions by turning off the saving of browser history. In Firefox:
The steps for the Mozilla Suite are similar