780123 - [New Tab Page] Use the hiddenWindow to preload a single newtab page that then serves multiple windows

Status: RESOLVED FIXED

(Firefox :: Tabbed Browser, defect)

Description

[Tim Taubert [:ttaubert] (inactive)]

Attachment: patch v1

From bug 753448 comment #45:

"It would be nice to have a single pre-loaded new tab page browser shared across all windows, but that seems more complicated (maybe we could investigate using the hidden window in a followup?)."

Comment 1

[:Gavin Sharp [email: [e-mail]]]

To deal with the non-privilegedness of the hidden window on Win/Linux in bug 762569, we switched to using an xhtml iframe (with bug 769771 fixed). We might be able to do something like that and just call swapFrameLoaders on it directly (not via browser.swapDocShells).

We'd also need to make sure the browser is destroyed when it's no longer needed (e.g. when there are no more open browser windows).

Comment 2

[Tim Taubert [:ttaubert] (inactive)]

(In reply to :Gavin Sharp (use [e-mail] for email) from comment #1)
> To deal with the non-privilegedness of the hidden window on Win/Linux in bug
> 762569, we switched to using an xhtml iframe (with bug 769771 fixed).

I tried doing the same but "about:newtab" wouldn't load because of security reasons. chrome://browser/content/newtab/newTab.xul loads just fine.

> We
> might be able to do something like that and just call swapFrameLoaders on it
> directly (not via browser.swapDocShells).

That's unfortunately not implemented for iframes :(

http://dxr.lanedo.com/mozilla-central/content/html/content/src/nsGenericHTMLFrameElement.cpp.html#l137

> We'd also need to make sure the browser is destroyed when it's no longer
> needed (e.g. when there are no more open browser windows).

We shouldn't do this because there wouldn't be any preloaded tab for newly opened tabs on Mac.

Comment 3

[Tim Taubert [:ttaubert] (inactive)]

Attachment: patch v2

Comment 4

[Tim Taubert [:ttaubert] (inactive)]

Comment on attachment 660815 [details] [diff] [review]
patch v2

Try says no.

Comment 5

[Tim Taubert [:ttaubert] (inactive)]

Attachment: patch v3

Comment 6

[Tim Taubert [:ttaubert] (inactive)]

Green on try (with browser.newtab.preload=true):

https://tbpl.mozilla.org/?tree=Try&rev=fa242a61c876

Comment 7

[Tim Taubert [:ttaubert] (inactive)]

This will work around the issue reported in bug 786484. With paint flashing enabled you can see that the excessive invalidation is gone.

Comment 8

[Jared Wein [:jaws] (please needinfo? me)]

Comment on attachment 661210 [details] [diff] [review]
patch v3

Review of attachment 661210 [details] [diff] [review]:
-----------------------------------------------------------------

I tested this out on Mac and confirmed that this fixes the invalidation issues.

::: browser/modules/BrowserNewTabPreloader.jsm
@@ +167,5 @@
>  
> +  _createPrivilegedFrame: function HostFrame_createPrivilegedFrame() {
> +    let doc = this._frame.document;
> +    let iframe = doc.createElement("iframe");
> +    iframe.setAttribute("src", "chrome://global/content/mozilla.xhtml");

Discussed on IRC and Tim said that we can add a chrome page specifically for new tab preloading.

Comment 9

[Jared Wein [:jaws] (please needinfo? me)]

r+ with the special-purpose chrome page for tab preloading.

Comment 10

[Tim Taubert [:ttaubert] (inactive)]

Thank you!

https://hg.mozilla.org/integration/fx-team/rev/90cc14017766

Comment 11

[Tim Taubert [:ttaubert] (inactive)]

Pushed a tiny bustage fix for xpcshell tests:

https://hg.mozilla.org/integration/fx-team/rev/47e7a44f9c91

Comment 12

[Tim Taubert [:ttaubert] (inactive)]

https://hg.mozilla.org/mozilla-central/rev/90cc14017766
https://hg.mozilla.org/mozilla-central/rev/47e7a44f9c91