Today I got an in-app message (and yesterday an email) from Tesla stating that they will be adding public (fast) chargers from third-party providers to the in-car navigation.
They will show up in the same place as the Destination Chargers. It also says they will keep improving this function with coming updates and keep adding new chargers.
It seems this is limited to The Netherlands, Belgium, Germany, Switzerland and Austria for now.
The message states they have already added them, although I cannot see any yet, but at least they are working on it!
https://www.reddit.com/r/teslamotors/co ... rs_to_the/