Blacklisting only works sometimes (flaky tests)

[dialex]

Current behavior:

I had 6 tests, all passed, all stable.

Now I have 20 tests, and previous stable tests are now flaky.

I blacklisted a domain (googlesyndication.com), but sometimes the request is not blacklisted and Cypress times out waiting for a reply. Why?

Am I missing something? Is there a workaround?

• This issue is very similar to Requests to blockHosts not being blocked consistently #2714, which is forgotten since Nov'18.
• Another user detected the same behaviour in Feb'19 HTTP requests time out when Cypress is executed within Docker and Jenkins #1039 (comment), but got no reply.
• And here I am now, Jul'19, worried that Cypress is not fit for purpose, just like this comment Page occasionally does not load from cy.visit() #2938 (comment) from the same user flagging the issue five months ago.

Desired behavior:

I want blacklisted domains to be ignored, always.

Versions

Cypress 3.2.0, MacOS 10.14.5, Chrome 75

[flotwig]

@dialex We've made a lot of network fixes between 3.2.0 and 3.3.2, could you let me know if you still experience this issue in 3.3.2?

If so, could you provide the full debug logs from when you experience the issue?

[dialex]

I upgraded to 3.3.2 and all tests are passing consistently: I got 5 runs all green, looks promising :)