Privacy Badger breaks Zendesk login on support sites with host mapping

[Rogdham]

What is your browser and browser version?

Firefox 93.0 (64-bit)

What is broken and where?

Zendesk login when using their host mapping feature (access the support website on your a custom domain).

• In Block cookies mode (default), the login page is displayed but the submit button is disabled (and a warning about cookies is displayed, see screenshot below)
• In Block entirely mode, nothing is displayed

What is the "culprit" domain?

For example on the support of Ankama which is a CNAME to ankama.zendesk.com.: blocked domain is ankama.zendesk.com

Note that assets.zendesk.com is in block cookies mode but that does not seem to be an issue.

What is your debug output for this domain?

**** ACTION_MAP for zendesk.com
zendesk.com {
  "userAction": "",
  "dnt": false,
  "heuristicAction": "cookieblock",
  "nextUpdateTime": 0
}
**** SNITCH_MAP for zendesk.com
zendesk.com [
  "insighttimer.com",
  "trustedsite.com",
  "bitfinex.com"
]

[ghostwords]

Hello and thanks for letting us know!

I only see the cookies message in Firefox. No message and the login button is active in Chrome. Does signing in work in Chrome, or is it also broken, just without notification?

[Rogdham]

No message and the login button is active in Chrome. Does signing in work in Chrome, or is it also broken, just without notification?

Indeed, but when submitting the form (with either valid or invalid credentials), the following message is displayed (sorry for the French):

This is in Block cookies mode (default), in Block entirely mode nothing is displayed (like in Firefox)