Currently, when an extension message listener fails to respond to a message, or to resolve the promise that its listener returns, the return channel stays open until the context is destroyed. We should try to handle this better for the case where the response callback or return promise is destroyed without ever being called or resolved, and close the response channels with an appropriate error.

Comment on attachment 8900008 [details] Bug 1389968 - Reject sendMessage() promise when response handle gets GCd https://reviewboard.mozilla.org/r/171340/#review178136 Thanks! ::: toolkit/components/extensions/ExtensionChild.jsm:28 (Diff revision 2) > > Cu.import("resource://gre/modules/Services.jsm"); > Cu.import("resource://gre/modules/XPCOMUtils.jsm"); > > +XPCOMUtils.defineLazyServiceGetter(this, "WitnessService", > + "@mozilla.org/toolkit/finalizationwitness;1", "nsIFinalizationWitnessService"); Should probably be called something like `finilizationService`.

Comment on attachment 8900008 [details] Bug 1389968 - Reject sendMessage() promise when response handle gets GCd https://reviewboard.mozilla.org/r/171340/#review178176 lgtm

Pushed by tomica@gmail.com: https://hg.mozilla.org/integration/autoland/rev/c4eec1e81c10 Reject sendMessage() promise when response handle gets GCd r=kmag

Is manual testing required on this bug? If yes, please provide some STR and the proper extension(if required) or set the “qe-verify -“ flag. Thanks!

Not needed here, thanks.