[interf4ce]

It can be, see Global Privacy Control [1]. As an example, the Complianz consent plugin for WordPress can detect and respect the user's GPC setting, but that feature can be toggled. So even though this exists, many sites will still ignore it.

1. https://globalprivacycontrol.org/

[jurgenburgen]

> GPC signal not detected.Please download a browser/extension that supports it.

Doesn’t seem to be widely adopted.