Read the statement by Michael Teeuw here.
UNSOLVED National Flag in Calendar Entry (Germany)
I have subscribed to the Google Calendar of public holidays (Germany). Our national public holiday is approaching, Oct 3. The standard calendar module does show this entry, but without the German national flag symbol. Instead, there are only two empty boxes in front of the entry. This is just a minor problem and I ignored it until today, when I discovered that when using the MMM-Remote-Control module on my iPad and mirroring the screen to my iPad the flag is there. So I assume that the Raspberry browser is not able to display this symbol. Any idea? Screenshot attached is from my iPad. I have Raspian and MM2, freshly installed. Thanks a lot! Bertram