1888715 - When changing VPN servers, Firefox crashes

Status: UNCONFIRMED

(Core :: DOM: Navigation, defect)

Description

[Nax [:Naxterra]]

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:124.0) Gecko/20100101 Firefox/124.0

Steps to reproduce:

Open VPN - Proton / Windscribe
Enter a random site
Change VPN server
Firefox is not able to connect any site

Actual results:

Firefox can't connect to any sites and when I click on close, it becomes non-responsive and I have to force kill it.

Expected results:

When or if I change a VPN server, even reconnect to same server, it should connect normally, like Edge does.

Comment 1

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

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

Comment 2

[Sunil Mayya]

Thank you for reporting the issue.
I was not able to reproduce this issue with Mozilla VPN.
Could you please let us know which VPN you are using?
Kindly share the HTTP logs for the problematic scenario to help debug this issue further.

Comment 3

[Nax [:Naxterra]]

Attachment: Firefox crash during network change

Here is the HTTP log file. I am using Proton VPN.

Comment 4

[Sunil Mayya]

:NaxTerra, thank you for the logs. I am assuming you are using the Proton VPN extension?

I see that the channels are canceled from nsDocLoader and scripts.
It may be a problem with the Proton VPN extension itself but first we need to establish the root cause for the cancellation of channels and the window becoming unresponsive.

To debug unresponsive window I would request for a profiler capture.
:NaxTerra: Could you please share profiler capture for this issue

2024-04-01 20:03:33.089000 UTC - [Parent 39236: Main Thread]: D/nsHttp nsHttpChannel::Cancel [this=26933795400 status=804b0002, reason=nsDocLoader::Stop]
2024-04-01 20:03:33.089000 UTC - [Parent 39236: Main Thread]: D/nsHttp nsHttpChannel::CancelInternal [this=26933795400]
....
2024-04-01 20:03:34.847000 UTC - [Parent 39236: Main Thread]: D/nsHttp nsHttpChannel::Cancel [this=26935153400 status=804b0002, reason=nsDocLoader::Stop]
2024-04-01 20:03:34.847000 UTC - [Parent 39236: Main Thread]: D/nsHttp nsHttpChannel::CancelInternal [this=26935153400]
...
2024-04-01 20:04:35.998000 UTC - [Parent 39236: Main Thread]: D/nsHttp nsHttpChannel::Cancel [this=26935156400 status=804b0002, reason=nsDocLoader::Stop]
2024-04-01 20:04:35.998000 UTC - [Parent 39236: Main Thread]: D/nsHttp nsHttpChannel::CancelInternal [this=26935156400]
....
2024-04-01 20:05:34.585000 UTC - [Parent 39236: Main Thread]: D/nsHttp 269387d0c00 called from script: resource://gre/modules/SearchSuggestionController.sys.mjs:357:35
2024-04-01 20:05:34.585000 UTC - [Parent 39236: Main Thread]: D/nsHttp nsHttpChannel::CancelInternal [this=269387d0c00]

2024-04-01 20:05:39.188000 UTC - [Parent 39236: Main Thread]: D/nsHttp nsHttpChannel::Cancel [this=2693bc7a800 status=804b0002, reason=CanonicalBrowsingContext::CanonicalDiscard]
2024-04-01 20:05:39.188000 UTC - [Parent 39236: Main Thread]: D/nsHttp 2693bc7a800 called from script: chrome://browser/content/tabbrowser.js:4362:15
2024-04-01 20:05:39.188000 UTC - [Parent 39236: Main Thread]: D/nsHttp nsHttpChannel::CancelInternal [this=2693bc7a800]
....

Moving this to DOM:Navigation to further analyze the root cause of these cancelled requests.

Comment 5

[Nax [:Naxterra]]

Attachment: Firefox 2024-04-02 16.25 profile.json.gz

I am using ProtonVPN Desktop app with split tunneling set to include to browsers (Edge and Firefox). ProtonVPN browser extension is installed but it is not active.

Comment 6

[Peter Van der Beken [:peterv]]

Could you try to reproduce in troubleshoot mode to rule out any extensions-related issues?
Also, where in the attached profile was the VPN switched?

Comment 7

[Nax [:Naxterra]]

In troubleshoot mode connections are working. I have no idea what is causing the issue because my current extensions are not touching the connections.

I have only one profile.

Comment 8

[Peter Van der Beken [:peterv]]

You could disable all extensions and reenable them one by one to find the culprit.

Comment 9

[Nax [:Naxterra]]

It doesn't look like an addon problem. I disabled all of them but still I have the issue. Edge doesn't have this problem.

My installed extension are below.
1Password Beta
Alldebrid
Facebook Container
FBCleaner
Firefox Multi-Account Containers
IDM Integration Module
NX Enhanced
SimpleLogin
Sponsorblock for Youtube
Startpage
uBlock Origin

On Edge I have the same extensions, except for Facebook Container, FBCleaner, and Firefox Multi-Account Containers.

I also tried disabling DNS over HTTPS (it is set to Max security), also tried with different DNS provider, but still the same issue. Firefox is not connecting to any websites, and it is not closing itself when I click on X button on top right.

Comment 10

[Nax [:Naxterra]]

Even with the new version 125 it is happening.