Install Matomo (on a server without Internet) and play!
For the first installation, when I first try to connect Matomo, it is so slow!!! (at first, only timeouts then after updating the max processing time to 1 minute a very slow interface)
During installation process, the wizzard should ask if the server will have an access to the Internet (or just check that one is available... ?) in order to set the proper value for
enable_internet_features and be able to use the Matomo just after the installation, without having to crawl almost the whole Matomo knowledge base to find the so simple solution:
(not so simple to find because when you encounter the slowness, you don't imagine it can come from the internet connection...)
Or at least add some warning in the system check...
I imagine that if for a reason or another the Matomo server looses the Internet access (example, the service in charge of firewalls create a new rule without informing other services), the very slow behaviour (or even timeouts) would happen, then I think the Matomo service should not try to connect the Internet at every request. Once a day or once an hour would be sufficient enough.
Install Matomo (on a server without Internet) and ~play~ wait!
Installation of a fresh Matomo instance.
I labelled this as (potential) bug because I think that new users could be quickly discouraged to use Matomo whereas it can be fixed easily.
Asking if the server has connection to the internet within the installation process sounds like a viable solution.