Compliance - adoption to the requirements of the §25 TTDSG (German law): Option to avoid the use of screen resolution params for a website-operation without Consent Banner

The reason for this feature request is a new German law that came into force on 1 December 2021. In the guidance of the Conference of German Independent Data Protection Authorities of the 20th of December 2021 is stated that a Consent Banner is not required if "only information, such as browser or header information, is processed which is transmitted necessarily (i.e. by Http-Protocoll definition) or due to browser settings (i.e. dnt is on) from the end-user device when a telemedia service is accessed Examples are:

  • the public IP address of the terminal device,
  • the address of the website called up (URL),
  • the user agent string with browser and operating system version, and
  • the language set.
    In contrast, it is already to be considered as accessing information on end-user devices if properties of an end-user device are actively read and transmitted to a server for the creation of a fingerprint (for example, by means of JavaScript code).

Source:, see Chapter 3.I.c), available only on German, sorry. I’ve translated the relevant text here above.

Screen resolution parameters are accessed in Matomo (see at the end-user device by matomo.js (aw.clientWidth, aw.clientHeight) and probably used in Matomo’s Universal Device Detection library to detect the device and the model used.
For some controllers of a telemedia this migth be a necessary function, but better there should be an option for the admins to explicitly abstain (i.e. by deselecting an option) from accessing the screen resolution parameters through accessing the information on end-user devices.


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Thank you so much for quick and helpfull answer. Matomo-Team is the best! :slight_smile: :sunglasses:
Tested with Matomo 4.7.1 and 4.10.1.