Is it possible, when using the on-premise version of Matomo, to use the ‘log analytics’ method by default, but enable the ‘javascript tracking’ on a user-by-user basis if they opt in?
Further context:
According to the PECR we cannot create or access a cookie on a user’s device for non-essential purposes without consent. According to the ICO, the GDPR’s definition of consent applies here, which means it needs to be an explicit opt-in. Also according to the ICO, web analytics is not essential. Therefore, we cannot use the ‘javascript tracking’ unless the user gives consent, as you set a cookie in order to do this (unless I’m mistaken?) Obviously, we don’t want to completely lose tracking if the user does not consent, so we would like to be able to fall back to the ‘log analytics’ method.
Furthermore, GDPR recital 30 makes it clear that cookies that contain identifiers are to be considered personal data and are therefore subject to the GDPR. (See “Cookies and the GDPR” on Cookies, the GDPR, and the ePrivacy Directive - GDPR.eu)
This means that a cookie containing an identifier needs explicit opt-in for both GDPR and PECR compliance.
FYI, I also contacted Matomo by email, and I have had a response.
Being able to run both log analytics and javascript tracking on a website at the same time is currently not possible and is on their backlog as an unscheduled idea.
They did bring my attention to the fact that you can disable cookies on their javascript tracking solution. I have not yet looked into this to make sure it is possible to disable cookies on their javascript tracking solution BEFORE any cookies are set.