1737177 - Add `nsSystemInfo` runtime flag for whether running application is running under Microsoft Windows S Mode

Status: VERIFIED FIXED

(Firefox :: Installer, enhancement, P3)

Description

[Nick Alexander :nalexander [he/him]]

To adjust behaviour depending on whether the application is running under Microsoft Windows S Mode, we'll need a runtime flag. https://docs.microsoft.com/en-us/uwp/api/windows.system.profile.windowsintegritypolicy?view=winrt-22000 suggests there are APIs for discovering this, and they’re definitely in the WinRT headers, so we should be able to just ask the system for these details.

Note to self: on my system, c:/Program Files (x86)/Windows Kits/10/Include/10.0.19041.0/cppwinrt/winrt/Windows.System.Profile.h looks to have the expected functions exposed.

Comment 1

[[e-mail] (:bhearsum)]

Attachment: Bug 1737177: Add `nsSystemInfo` runtime flag for whether running application is running under Microsoft Windows S Mode. r=mhowell!

This patch uses the Windows.System.Profile.WindowsIntegrityPolicy class to determine whether or not Windows is in S mode. This class is only available beginning with SDK 17763 (newer than what we use right now), so we need to fetch it at runtime with some magic.

I was able to test this on a couple of Windows 10 systems, and verifying that it was set to false (by dumping Services.sysinfo to the console). I'm not aware of a way to test that it detects S mode properly until we can get a copy of Firefox with this code in it into the Store, so it can be installed on an S mode machine -- but the tests I have done appear to confirm that we're fetching the class and calling its method properly (early attempts here resulted in crashes due to access violations).

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/2dc54f256ad3
Add `nsSystemInfo` runtime flag for whether running application is running under Microsoft Windows S Mode. r=mhowell

Comment 3

[[e-mail] (:bhearsum)]

Attachment: Bug 1737177: Add a string to about:support when Windows is in S Mode. r=mhowell!

This is not strictly necessary, but it's probably useful to have, and will aid QA in verifying the original patch in this bug.

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/4ca4d5cbfc62
Add a string to about:support when Windows is in S Mode. r=mhowell

Comment 5

[Norisz Fay [:noriszfay]]

https://hg.mozilla.org/mozilla-central/rev/2dc54f256ad3

Comment 6

[Alexandru Michis [:malexandru]]

https://hg.mozilla.org/mozilla-central/rev/4ca4d5cbfc62

Comment 7

[Masatoshi Kimura [:emk]]

This bug assumes that MSIX packaged Firefox will work in S-mode, but apparently it does not. See bug 1741539.

Comment 8

[[e-mail] (:bhearsum)]

(In reply to Masatoshi Kimura [:emk] from comment #7)

This bug assumes that MSIX packaged Firefox will work in S-mode, but apparently it does not. See bug 1741539.

As I noted in that bug, we've explicitly disabled S mode installs for now, so this is future looking work for after we've re-enabled it.

Comment 9

[Alexandru Trif, Desktop QA [:atrif]]

Hello! Are there any steps we could use to test this or it cannot be tested yet because MSIX is blocked in Windows S Mode? Thank you!

Comment 10

[[e-mail] (:bhearsum)]

(In reply to Alexandru Trif, QA [:atrif] from comment #9)

Hello! Are there any steps we could use to test this or it cannot be tested yet because MSIX is blocked in Windows S Mode? Thank you!

Not quite yet, because of the block you mentioned. I'm looking into setting up a separate App on the Store that we can test with, though. I'll be in touch when it's possible to verify this.

Comment 11

[Nick Alexander :nalexander [he/him]]

(In reply to [e-mail] (:bhearsum) from comment #10)

(In reply to Alexandru Trif, QA [:atrif] from comment #9)

Hello! Are there any steps we could use to test this or it cannot be tested yet because MSIX is blocked in Windows S Mode? Thank you!

Not quite yet, because of the block you mentioned. I'm looking into setting up a separate App on the Store that we can test with, though. I'll be in touch when it's possible to verify this.

My preference is to get Firefox Nightly into the Store, possibly with a private audience, so that we can use it for this type of QA testing (and we can leave it available for Windows S Mode). But that's blocked (for me, at least) on a very strange behaviour with package identifiers in the Store. I had one frustrating interaction with the Store support folks and have emailed another MS contact about this behaviour, but no reply yet. We'll have to escalate to get this addressed, it seems.

Comment 12

[Masatoshi Kimura [:emk]]

Unfortunately Firefox 96 did not show SMode-ness correctly in about:support.
Services.sysinfo.processInfo.isWindowsSMode should be (await Services.sysinfo.processInfo).isWindowsSMode.

Comment 13

[[e-mail] (:bhearsum)]

Attachment: WIP: Bug 1737177: fix about:support display of S mode

Comment 14

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/8e42c80a077b
WIP: Bug 1737177: fix about:support display of S mode r=nalexander

Comment 15

[Marian-Vasile Laza]

https://hg.mozilla.org/mozilla-central/rev/8e42c80a077b

Comment 16

[BugBot [:suhaib / :marco/ :calixte]]

Change the status for beta to have the same as nightly and release.
For more information, please visit auto_nag documentation.

Comment 17

[Masatoshi Kimura [:emk]]

Verified fixed with 98.0.1.