we keep running into the same problem with OneTrust:
OneTrust runs an automatic cookie scan
OneTrust identifies cookies that Piwik PRO use’s but only once a user has given consent
OneTrust auto blocks the Piwik PRO script so that it is only being placed if a user has accepted performance cookies. That means we can not track anonymous traffic.
For now, our solution is deleting the Piwik PRO Cookies out of the OneTrust backend. But the scan happens 2-3 times a month. There has to be another solution to be able to track anonymous traffic.
The OneTrust integration itself works fine.
Has anyone had the same issue and has found a solution?
Did you try to add the required cookies manually in OneTrust, so they won’t be overwritten by a OneTrust cookie scan. I know some sites use it like this.
When OneTrust does its auto scan it categorizes cookies like _pk_id as a third-party cookie. In the Piwik PRO over view, it states that it is a first-party cookie.
Just for my understanding, would we manually list all cookies e.g. _pk_id manually as first-party cookies, right?
thank you so much for your support and the quick replies.
Do you know how your other clients have categorized the Piwik PRO Cookies inside of OneTrust? I think to avoid the script being auto-blocked we would have to categorize all cookies as strictly necessary.
If you use anonymous tracking without cookies, there is no need to add the pk_ cookies as strictly necessary. If you have a setup for 30 minute cookies, you need to set it as necessary.
ppms_privacy_ is necessary to store the consent state.
The other cookies are based on the type of triggers and tags you have setup (have a look at the initially shared page on regarding the cookies, we tried to describe it as detailed as possible per type of cookie)