1782698 - issues with MS Application Guard and Firefox Dev. Edition (104.0b4 (64-Bit)), blocking ALL pages

Status: RESOLVED INCOMPLETE

(Core :: Security: PSM, defect)

Description

[Tommi]

Attachment: 2022-08-02_132551.png

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Firefox/91.0

Steps to reproduce:

activated MS Application guard on the Windows , added application guard to FF 103 (all went well)
Edition Windows 10 Enterprise
Version 20H2
Betriebssystembuild 19042.1826
Leistung Windows Feature Experience Pack 120.2212.4180.0

updated from 103 to 104.0b4 (64-Bit).

Actual results:

all pages not loading, tab is flickering and resulting in an error msg.
checking the certificate, page doesn't show any.
after around 10sec, even not the flickering is seen
developertools report "blocked by Application Guard".
User-Agent
Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:104.0) Gecko/20100101 Firefox/104.0

Expected results:

load pages as done in 103

Comment 1

[Tommi]

Attachment: 2022-08-02_134404.png

Comment 2

[Tommi]

Attachment: 2022-08-02_134453.png

Comment 3

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

The Bugbug bot thinks this bug should belong to the 'Core::Security: PSM' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 4

[Dana Keeler (she/her) [:keeler]]

(In reply to Tommi from comment #0)

developertools report "blocked by Application Guard".

So the add-on you installed is blocking the pages you're trying to load? It sounds like the add-on is either broken or misconfigured. Can you file a bug against it?

Comment 5

[Tommi]

the MS Application guard plugin worked well on 103 and and the versions below and is configured quite well, but with updating dev edition to 104 pages don't load anymore. not sure if this incompatibility is caused by the plug in or if any changes on FF 103-104 are the root for it. As said this appears just on the 104. https://addons.mozilla.org/de/firefox/addon/application-guard-extension/

Comment 6

[Dana Keeler (she/her) [:keeler]]

Would you be able to use https://mozilla.github.io/mozregression/ to narrow down when it stopped working? Thanks!