1234700 - Hide window.showModalDialog, at least when e10s is enabled

Status: RESOLVED FIXED

(Core :: DOM: Core & HTML, defect)

Description

[Masatoshi Kimura [:emk]]

The broken feature is worse than no feature because the former will hinder feature detection.
This is not a theoretical possibility. The broken showModalDialog breaks at least  Office 365 and Exchange 2013. See bug 1077002 comment #13 and onwards.

Comment 1

[Masatoshi Kimura [:emk]]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=d21b68c0775f

Comment 2

[Masatoshi Kimura [:emk]]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=e247bc83b16f

Comment 3

[Masatoshi Kimura [:emk]]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=3477c107fabc

Comment 4

[Masatoshi Kimura [:emk]]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=73e1ccc19b2d

Comment 5

[Masatoshi Kimura [:emk]]

Attachment: Hide window.showModalDialog when e10s is enabled

Comment 6

[:Ms2ger (he/him; ⌚ UTC+1/+2)]

lgtm, fwiw

Comment 7

[Masatoshi Kimura [:emk]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/1b9b9c8d4207d31b9de8adb21404bb9a584485b5
Bug 1234700 - Hide window.showModalDialog when e10s is enabled. r=jimm

Comment 8

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/1b9b9c8d4207

Comment 9

[Kohei Yoshino]

Posted the site compat doc: https://www.fxsitecompat.com/en-US/docs/2015/showmodaldialog-has-been-disabled-in-multi-process-firefox/

Comment 10

[Masatoshi Kimura [:emk]]

(In reply to Kohei Yoshino [:kohei] from comment #9)
> Posted the site compat doc:
> https://www.fxsitecompat.com/en-US/docs/2015/showmodaldialog-has-been-disabled-in-multi-process-firefox/

> showModalDialog has been disabled in multi-process Firefox

I think the term "disable" is obscure here. Prior to Firefox 39, showModalDialog always threw NS_ERROR_UNEXPECTED in e10s. Firefox 39 changed the logic to check e10s explicitly and throw NS_ERROR_NOT_AVAILABLE if in e10s. This bug removed showModalDialog itself from the window object, but showModalDialog was already "disabled" in e10s.

> At least Office 365 and Exchange 2016 are known to be broken due to the missing showModalDialog.

They are broken due to present-but-unworking showModalDialog. They will work if showModalDialog is missing because they use feature detection. This bug will *fix* them in e10s.

Comment 11

[Jean-Yves Perrier [:teoli]]

As this is not the default, I have added a comment in
https://developer.mozilla.org/en-US/Firefox/Releases/46#DOM_HTML_DOM
only

Comment 12

[Kohei Yoshino]

(In reply to Masatoshi Kimura [:emk] from comment #10)
> (In reply to Kohei Yoshino [:kohei] from comment #9)
> I think the term "disable" is obscure here. Prior to Firefox 39,
> showModalDialog always threw NS_ERROR_UNEXPECTED in e10s. Firefox 39 changed
> the logic to check e10s explicitly and throw NS_ERROR_NOT_AVAILABLE if in
> e10s. This bug removed showModalDialog itself from the window object, but
> showModalDialog was already "disabled" in e10s.

Thanks for your clarification. I'm adding the details to the doc. The title may be okay if explained well.