Octoprint crashes with Mini 5.1.0-alpha1 firmware

Updated mini with 5.1.0-alpha1 firmware and very impressed, however using octoprint Version 1.9.3 from rpi4, crashes printer to a bsod. process: Printer at idle, with octoprint logo, initiate print and mini reboots and received BSOD.
"FSM Types.cpp:333
fsm create:serial printing alread opened at level 0.
Called from static void gcodesuite::M876() .....
Gcode generated with prusa slicer 2.6.1. input shaper is a game changer, works amazing from usb thumb. 2.5 hr print down to 39min

Please advise if this is an octoprint issue or a prusa issue.

More than likely a firmware related issue not OctoPrint if it was working previously. Keep in mind, running any kind of firmware that is not stable (ie alpha, beta) then more than likely it's going to be an issue on that side.