Cookie consent segmentation doesn't update if a user changes consent

[MaticSulc]

I have followed this guide, it works as expected on frontend. My consent handler calls _paq.push(["forgetCookieConsentGiven"]);, cookies get removed and don't reapply on load.

If I look in the matomo dashboard, I have created segments based on Profilable fields.

Example:
User comes on the website for the first time. Until they accept the consent, they are profiled in the "no cookie consent given" segment. When they do, it gets moved to the "consent given" segment. If they never accept it, they are not moved and stay there - as expected,

Now if a user changes their cookie consent and decides to block ads, my matomo dashboard keeps showing them in the "cookie consent given" segment. I don't think this is expected behaviour. I would expect that they start to get tracked in the "no cookie consent" segment, but everything they consented to is kept in the other one.

Looking forward to any opinions :)

Environment

• Matomo Version: 4.13.3
• PHP Version: 8.1.16
• Server Operating System: Linux

[bx80]

Thanks for reporting this @MaticSulc, that doesn't sound like correct behavior.

Could you share the details of the "no cookie consent " and "consent given" segments you are using? This will help us recreate the problem.

[MaticSulc]

I am using the "Profilable" field, as stated in the tutorial. :)

For cookie consent given, the field is supposed to be 1. And vice versa, 0 for o consent.

[bx80]

Thanks @MaticSulc, I missed that you were using the Profilable field 👍

From looking at the profilable field code it seems that not updating this field when cookie consent is withdrawn is intentional due to the way visitor recognition currently works.

This behaviour doesn't produce an ideal outcome for segmentation, and could benefit from a re-evaluation and additional documentation. I've assigned this issue for prioritization.

[atom-box]

A user writes the following:

"As I just recently activated cookieless tracking on one of our websites, I am interested in how this affects the total numbers etc. That's how I found this article, which is very helpful.

But here's one thing that surprised me a little:

• When a visitor first denies all cookies, she/he is first listed in the "no cookie consent given" segment. Great.
• Once this particular user activates cookies, she/he will be listed in the "cookie consent given" segment and disappears in the no consent segment. That's great, too.
• If one however decides to take back that decision and the user doesn't want to allow cookies anymore after a while (for whatever reason), they will still be found in the "cookie consent given" segment. That is including all their future clicks, and after explicitly denying cookie-based tracking.

So it's kind of once accepted, always accepted, am I right?

It doesn't seem to rely on a cookie being set, as I tried this with a new inkognito window. Maybe this is rather based on a matomo-based ID?

Is there a way to cope with that rather inaccurate segmentation?
Is this a bug?