I'm not sure which is worse: not validating your data, or silently truncating invalid data.

It seems that the fix [1] was to limit the length of email addresses to 127 characters. That'll do for the time being, but they really should pay more attention to database warnings. MySQL does all sorts of stupid things, but at least it tends to emit warnings when it's being stupid. Catching those warnings and turning them into exceptions should go a long way toward preventing bugs like this.

[1] https://git.mozilla.org/?p=bugzilla/bugzilla.git;a=commitdif...