Currently we know an app is launched by webapps-launch event. (It was mozChromeEvent:webapps-launch in the past). It's better if we know who is the launching the app, with this we could establish relationships between apps. For example, homescreen is the launcher of most apps, so if an app is terminated in foreground we could just reopen the launcher(homescreen app). For example, settings app is the launcher of keyboard settings app so if it's closed in foreground we could just reopen the launcher(settings app). If the launcher is system app we could just open the homescreen. A clear relationship map between all windows make us have a better management.

Taken.

Implementation proposal: 1. Remove 'webapps-launch' observer in shell.js 2. Add 'webapps-launch' observer in BrowserElementChildPreload 3. Try to figure out how to identify docShell or something like that in http://mxr.mozilla.org/mozilla-central/source/dom/apps/src/Webapps.jsm I guess the API call is also in child process so we won't hurt the launch time?

Fabrice, let me know your thought to this idea. Thanks!

OK I find one problem: If we are going to implement "open the app from application list in settings app" then the parent of the new app would be settings, this doesn't make sense. :/

Yes, not all events make sense as mozbrowser events. In this case, we also have runtimes that don't use mozbrowser at all and that we need to support as well. I tend to think that this one should be a WONTFIX.

Make beta clear

I am closing this one but we still have the use case in comment 0. Open another bug for that.