Set reasonable default lifetimes for all mtm_consent_* and matomo_ignore cookie

[peterbo]

Summary

Consent-Cookies and matomo_ignore cookies are set for a lifetime of 30 years or even without any expiration time (https://matomo.org/faq/general/faq_146/). You can set the lifetime of the consent cookies as a second method parameter, but there should be a sane default lifetime set to e.g. 13 to 20 months. The different regulators demand different lifetimes for the cookies, but also for consent cookies, these are mostly 6 to 13 months. See https://iapp.org/media/pdf/resource_center/CNIL_ICO_chart.pdf

The CNIL for example states "As a best practice, the French regulator considers that consent given to cookies should be valid for six months but emphasizes that there is no perfect “one size fits all” answer to this question.".

U.K. regulation: "The maximum possible technical duration of a cookie (e.g., “31/12/9999”) would not be regarded as proportionate in any circumstances."

The lifetime of the matomo_ignore cookie can't be changed at all as far as i know. This should also have a reasonable default lifetime.

Your Environment

• Matomo Version:
• PHP Version:
• Server Operating System:
• Additionally installed plugins:

[randy-innocraft]

Hi @peterbo,
Thank you for bringing this to our attention and for your valuable input.
Your suggestion seems like a valuable enhancement to our product.
We will forward this to our Product team for review and future consideration.
If you have any additional details or questions, please feel free to share them here.