title: The same Unicode character sometimes appears as solid black and sometimes a colored icon
body: <p>I offer a team calendar via Google Calendar to our sports club. It contain all match appointments for several teams and sports (like soccer, tennis, dart...).
  I put Unicode icons at the beginning of the subject like a dartboard and a house for a dart match at our home location and a car for outside.</p>
  
  <p>Like this:  DC Flight Control - Team Dart Donkies</p>
  
  <p>On Smartphones the icons appears as a colored image.<br>
  In browsers on a Win7 system as a solid black icon.<br>
  On my Win10 system also as colored image.</p>
  
  <p>Same Google-Account, same view, same Google-Settings...</p>
  
  <p>Is this a windows depending thing? Anybody can explain?</p>