1936452 - Firefox on MacOS Sequoia fails to use manual proxy

Status: RESOLVED DUPLICATE of bug 1919889

(Core :: Widget: Cocoa, defect)

Description

[Clifford Heath]

Attachment: Screenshot 2024-12-11 at 11.39.03 am.png

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/18.1.1 Safari/605.1.15

Steps to reproduce:

I use Firefox with a manual web proxy pointing at a server on my LAN.
I upgraded MacOS to Sequoia, and now Firefox fails to connect to the proxy.
The proxy is available; I can use telnet and curl to get to it, see screenshot.
Firefox works normally if the proxy is disabled, but I need it to use this proxy.

window.navigator.userAgent:
"Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:133.0) Gecko/20100101 Firefox/133.0"

$ uname -mrsv
Darwin 24.1.0 Darwin Kernel Version 24.1.0: Thu Oct 10 21:03:11 PDT 2024; root:xnu-11215.41.3~2/RELEASE_ARM64_T6020 arm64

Actual results:

"The proxy server is refusing connections"

Expected results:

Normal browsing behaviour via the proxy

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

[Haik Aftandilian [:haik]]

@Clifford, thanks for the report. Could you check if Firefox is enabled in your macOS System Settings -> Privacy & Security -> Local Network?

The Local Network permission is new in macOS 15 and we've had reports the user is not always prompted to enable the setting.

The kernel version you posted (24.1.0) maps to macOS 15.1 so I don't think this applies, but FYI Apple's docs state "macOS 15.1 fixed a number of local network privacy bugs. If you encounter local network privacy problems on macOS 15.0, retest on macOS 15.1 or later."

Comment 3

[Clifford Heath]

Indeed this fixed my problem. And no, I was not prompted. It is Sequoia 15.1.1

Comment 4

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

The severity field is not set for this bug.
:spohl, could you have a look please?

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