IceGenerateMagicCookie uses arc4random_buf from libbsd0: https://cgit.freedesktop.org/xorg/lib/libICE/tree/src/iceauth.c?h=libICE-1.0.9#n68
I am pretty sure that this bug is another symptom of #898088: Bug#898088: arc4random_buf() may block for a long time https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=898088 I will merge them. Kind regards, -- Ben Caradoc-Davies <[email protected]> Director Transient Software Limited <https://transient.nz/> New Zealand

