1872233 - Firefox does not work while using a VPN on macOS

Status: UNCONFIRMED

(Core :: Widget: Cocoa, defect, P5)

Description

[me]

Attachment: zip file containing mkv recording of issue

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:121.0) Gecko/20100101 Firefox/121.0

Steps to reproduce:

In order to ensure any possible factors were ruled out, I tested the combination of the following:

• Enabled/Disabled custom DNS .mobileconfig (Adguard DOH)
• Enabled/Disabled Firefox DOH (Default Cloudflare resolver)
• Removed all profiles to ensure extensions/cache was not interfering

Product-specific information:

• 2020 M1 Macbook Air - macOS Sonoma
• Firefox 121.0 (Latest as of today)
• PrivateInternetAccess VPN

Actual results:

When using a VPN (specifically, PrivateInternetAccess) Firefox fails to work. Typing in, for example, "google.com" just causes the search bar to reset-- it's like Firefox doesn't even attempt to resolve the domain. As such, I tried configuring different DNS (using my .mobileconfig AdGuard DOH, using default ISP DNS, using Firefox's Cloudflare DOH, etc) and the issue persists regardless of the configuration used.

I confirm this is a Firefox specific issue as dig, curl, and nslookup all work regardless of being on the VPN or not. Additionally, tested Safari and it works regardless of VPN status.

Expected results:

Searches should work while using a VPN.

Comment 1

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

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

Comment 2

[Stephen A Pohl [:spohl]]

I can confidently confirm that Firefox works properly with PrivateInternetAccess. Have you tested in Safe Mode? Have you restarted Firefox after enabling the VPN? Have you reset PIA to default settings?

Comment 3

[me]

(In reply to Stephen A Pohl [:spohl] from comment #2)

I can confidently confirm that Firefox works properly with PrivateInternetAccess. Have you tested in Safe Mode? Have you restarted Firefox after enabling the VPN? Have you reset PIA to default settings?

I tested it by deleting all profiles and restarting Firefox in-between deletions. I can test Safe Mode as well, but figured no addons, fresh profile == safe mode. I can also try resetting PIA to default settings, but I tried different configurations with PIA as well (WireGuard, OpenVPN, PIA DNS, Built-in DNS, etc.) PIA works on Safari, curl, nslookup, dig, etc., so leads me to believe it isn’t a PIA setting(s) issue, but won’t hurt to confirm.

Comment 4

[me]

(In reply to Stephen A Pohl [:spohl] from comment #2)

I can confidently confirm that Firefox works properly with PrivateInternetAccess. Have you tested in Safe Mode? Have you restarted Firefox after enabling the VPN? Have you reset PIA to default settings?

Tested Safe Mode, reset PIA to default settings— issue persists. Tested PIA with Chrome, works fine. Downloaded Firefox Nightly, issue persists. However, on Nightly I was able to get it to produce “Connection reset” instead of just resetting the search bad upon entering, so atleast there’s an error now.

Comment 5

[me]

Further testing: I updated PIA to the latest beta version and also downloaded ProtonVPN to see if it reproduces across different VPN solutions.

Tested ProtonVPN, everything appears to work.
Updating to PIA Beta seems to resolve some issues:

• google.com resolves
• bing.com resolves
• youtube.com resolves (but shows that I am offline, see below)
• twitter.com resolves (but displays "Something went wrong", see below)

This isn't extensive testing, but now it's resolving unlike before. However, the most prevalent issue I am seeing is related to nameservers. See attached:

https://i.imgur.com/5SepFci.png
https://i.imgur.com/W3lbVMa.png
and then certain sites don't resolve at all, ie https://i.imgur.com/3svvgVg.png

Comment 6

[me]

(In reply to me from comment #5)

Further testing: I updated PIA to the latest beta version and also downloaded ProtonVPN to see if it reproduces across different VPN solutions.

Tested ProtonVPN, everything appears to work.
Updating to PIA Beta seems to resolve some issues:

• google.com resolves
• bing.com resolves
• youtube.com resolves (but shows that I am offline, see below)
• twitter.com resolves (but displays "Something went wrong", see below)

This isn't extensive testing, but now it's resolving unlike before. However, the most prevalent issue I am seeing is related to nameservers. See attached:

https://i.imgur.com/5SepFci.png
https://i.imgur.com/W3lbVMa.png
and then certain sites don't resolve at all, ie https://i.imgur.com/3svvgVg.png

Would like to reiterate however, that PIA works fine on Safari, Chrome, and other applications. One thing I will note about PIA vs ProtonVPN is that ProtonVPN installs a VPN configuration profile, whereas PIA doesn't. :shrug:

Comment 7

[Stephen A Pohl [:spohl]]

Have you tested different VPN servers in the PIA settings? Does this reproduce for all of them? Also, have you tested different DNS settings in PIA?

Comment 8

[me]

(In reply to Stephen A Pohl [:spohl] from comment #7)

Have you tested different VPN servers in the PIA settings? Does this reproduce for all of them? Also, have you tested different DNS settings in PIA?

Tested 10 different servers (different countries) and it reproduces. Tested following DNS configurations and it persists:

• Built-in resolver (Adguard DOH)
• Custom PIA DNS (1.1.1.1)
• PIA DNS
• Disabling Adguard DOH and using built-in resolver with ISP DNS

I tested all these DNS settings (within PIA) as well as changing Firefox's DOH settings in the Settings > Security & Privacy tab, switching between 'Off' so my system DNS would take over and Firefox's Standard DOH (Cloudflare DOH). Issue persists regardless of the configuration being used and the DNS server being used.