Logins flaky from Chrome/Chromium (also Safari)

[jeepingben]

Explain what happens

1. Log in to Cockpit from an affected browser
2. Log out
3. Log in

Before too long (10-30 attempts) you will get a 'Connection Failure' or black screen. I spent quite a while trying to narrow this down and it appears to be something between those browsers and Cockpit.

I found this against Cockpit-310.4 (OL8) but reproduced it on Cockpit-223 (OL9) and Cockpit 332 (Fedora 41). I also downgraded cockpit on OL8 down to 286.1.

The browsers I used were generally quite clean - a fresh install of chromium-nightly on Linux, and docker images for Chrome/Chromium + Selenium: https://github.com/SeleniumHQ/docker-selenium/releases For Safari I used a private window.

Using Firefox does not show this issue. Can someone take a look?

Version of Cockpit

286.1-332

Where is the problem in Cockpit?

Unknown or not applicable

Server operating system

Fedora

Server operating system version

41

What browsers are you using?

Firefox, Chrome, Safari macOS

System log

`Feb 05 11:20:15 tenable-umwey6bv cockpit-ws[1486565]: request timed out, closing`
Is what I notice at the time of each failure.

[jeepingben]

It looks like tests (https://github.com/cockpit-project/cockpit/blame/310.4/.github/workflows/unit-tests.yml#L25 https://github.com/cockpit-project/cockpit/blob/main/test/browser/run-test.sh#L33) currently use firefox. I would expect this to be reproduced after a few runs if either of those switched to chromium/chrome. I was able to reproduce this interactively and via automation.

Doing this as quickly as possible is efficient, but not required. Inserting a 15 second delay between attempts still allows the problem to occur.

Failure-F41-15fps.mov