Right now we render the background page in a windowless docshell, which doesn't have a frameloader. In order to start running extensions out of process, we'll need to use a <browser> element so that we can set the remote attribute. My plan here is to create a windowless chrome docshell and put a content <browser> element inside it that would render the background page.

This is the patch we discussed today on IRC. Right now when you add a content docshell to a chrome docshell that was created with an nsWebBrowser, the content docshell doesn't get a tree owner. This patch creates a new tree owner for it. I tried to go with the simplest possible approach, since no one else is likely to use this code.

Comment on attachment 8686447 [details] [diff] [review] Allow windowless chrome docshells containing content docshells >+nsDocShellTreeOwner::EnsureContentTreeOwner() >+{ >+ if (mContentTreeOwner) >+ return; Always {} with if >@@ -786,16 +806,20 @@ nsDocShellTreeOwner::WebBrowser(nsWebBrowser* aWebBrowser) > RemoveChromeListeners(); > } > if (aWebBrowser != mWebBrowser) { > mPrompter = nullptr; > mAuthPrompter = nullptr; > } > > mWebBrowser = aWebBrowser; >+ >+ if (mContentTreeOwner) { >+ mContentTreeOwner->WebBrowser(aWebBrowser); make this if (mContentTreeOwner) { mContentTreeOwner->WebBrowser(aWebBrowser); if (!aWebBrowser) { mContentTreeOwner = nullptr; } } so that we clear the edge when webbrowser->Destroy() is called.

Kris, are you okay reviewing this?

Yeah, I don't see anything I'm not familiar with. I'll look at it tomorrow.

I guess the ext-utils.js thing you already fixed.

Comment on attachment 8689321 [details] [diff] [review] use <browser> element for background page Review of attachment 8689321 [details] [diff] [review]: ----------------------------------------------------------------- (In reply to Bill McCloskey (:billm) from comment #5) > I guess the ext-utils.js thing you already fixed. Yeah. I don't really care which fix we keep, just so long as we don't keep both.

https://hg.mozilla.org/integration/mozilla-inbound/rev/4b03b2f843a8 https://hg.mozilla.org/integration/mozilla-inbound/rev/0cb416a5606a

https://hg.mozilla.org/mozilla-central/rev/4b03b2f843a8 https://hg.mozilla.org/mozilla-central/rev/0cb416a5606a