Hi! First of all thank you very much for this recovery. It has everything needed to live in the “middle earth” of people that care about privacy but has to use everyday applications which need Google play services 
I’ve got a Samsung Galaxy S9 with TWRP 3.5.2 and after the first install everithing worked perfect -apart from a little problem with TWRP that I had also with my old phone, in which the recovery asks me for a password despite during the installation I didn’t encrypted the storage. If I remember well, using a microSD card should avoid problems with things to flash(I hope), but of course if you have any suggestion to resolve this problem without format the phone it would be really appreciated!-
The real problem I encountered is that the root permissions obtained with magisk have been disabled updating to version 1.2. The app indeed says that the root app is not installed. I’ve delayed to resolve this problem some months, but now that there is the update of August the 28th could be a good moment to try 
Do I have to re-flash Magisk after the update?
Thanks in advance