I have a existing installation on a RasPi 2. Is it possible to run this Installation on a Pi 4?
Its not as simple as removing the SD card from the 2, and plugging it into the 4.
Its not super complicated though.
You need to backup the pi2, then install freedombox on the pi4 (as a fresh install), then restore your data from the backup.
I would recommend that you DO NOT overwrite the data on the pi2 until you are 100% sure that the pi4 works the way you want.