Need a pref to manage external protocols, so that if a user allows or blocks a particular one they can later change their mind without having to know about or use about:config Possibly should also surface the pref setting for the default behavior (don't load, always load, ask). With the patch for bug 173010 "ask" is the initial setting.

From Bug 173010 comment #23 (Darin Fisher (IBM) said): I think that UI for this security feature should be a requirement for Firefox 1.0. We should probably leverage the "banner"-based UI notification, and provide a management interface similar to what is currently provided for other things like XPI whitelisting. Only, this would apply to URL schemes instead of hostnames.

Do we need to get UI additions/changes in before PR?

Not going to happen before PR.

Should this go into the file types list? That's how Windows handles it.

Does this have l10n impact? If so, you have about 24 hours to land the strings.

Not a "blocker"

if this is an urgent need, feel free to reopen.. probly as a front end bug tho