If you prefer to use a classic font like Arial instead of the system font or if you experience some problems with the system font in Matomo (Piwik) 3 install this theme.
How do I activate this theme?
Once you have installed and activated this plugin, go to "Administration => Plugins => Themes" and there you can activate it.
Will all users of my Matomo (Piwik) installation use this theme once activated?
Yes, in Matomo an activated theme always applies to all users.
View and download this plugin for a specific Matomo version: