Last night developers checked in a fix that makes it real easy to find your Breakpad crashes - simply type about:crashes in the URL bar and voila - a list of your crashes appear. There is even a way to clear the list. Currently this is only available on the trunk (The 2.0.0.x branch uses Talkback as a crash reporting tool).
If you do crash, it is always helpful to include as much information as possible. Breakpad will soon include a "Comments" field that will allow you type what you were doing when you crashed. This is often invaluable for our team and community, as it helps us identify trends of what people were doing when they crashed. Also, if you file a bugzilla bug and you have a reproducible crash, it is useful to include the Breakpad URL in the bug so the developers can look at the stack trace.