Investigate RangeError [ERR_SOCKET_BAD_PORT]: Port should be >= 0 and < 65536. Received type number (NaN) within firefox system-tests

[AtofStryker]

Current behavior

Currently, sometimes in CI after the merging of #30250, firefox fails to start with the error RangeError [ERR_SOCKET_BAD_PORT]: Port should be >= 0 and < 65536. Received type number (NaN). It looks like we are failing to parse the cdp port here. we should wrap this logic and handle the error to see what moz:debuggerAddress capability returns within our system-tests to see if we can fix the error or handle it more gracefully.

Below is a screenshot of the error, which can be seen in this job

Desired behavior

Once we see where the error is coming from, we can either resolve it completely or handle it more gracefully

Test code to reproduce

N/A

Cypress Version

N/A

Node version

N/A

Operating System

N/A

Debug Logs

No response

Other

No response

[AtofStryker]

I am seeing this still on the #30324, so this is something we need to handle. Its difficult to reproduce, but we can likely handle the issue in the case a CDP address is undefined and send a retry event to relaunch the browser. We send the capability, but it does not get set

[AtofStryker]

@whimboo any idea why this would happen? It seems very seldom, but sometimes when sending the moz:debuggerAddress the capability address comes back as undefined. I put together a work around in #30393 but overall seems odd.

[whimboo]

@AtofStryker would you mind running tests with the Firefox preference remote.log.level set to Trace? See our documentation for more details. It might indicate what's wrong. Only from the above output I cannot tell anything and I'm also not aware of such a problem on our side. It's basically new to me. Thanks.

[AtofStryker]

@whimboo I can. I have it enabled in this circleCI run which is this commit. It happens sporadically so I might not be able to reproduce it on first try (also going to be some failures from printing additional logs) but ill see if I can get a run where it fails with this issue.

[whimboo]

Yes, understood. Let me know when it happened next and I'll take a look at it. Thanks!