Big Sur beta 2, MBP 15" 2016 stuck at boot

After the installation of Big Sur beta 2, MBP 15" 2016 is stuck at the boot screen. After typing in the password.
Any solution to that?

In verbose mode, the last line is :

installGTK: GTK installed

After that it seems there is neverendig loop of several lines beginning all with :

ARPT:

The last one is :

ARPT: 1515.997036: txpktpend ACBK 0 ACBE 0 ACVI 0 ACVO 1 BCMC 0 ATIM 0
Same here for 2019 16 inch
Big Sur beta 2, MBP 15" 2016 stuck at boot
 
 
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