Comment 1 for bug 1955707

(a) It's better that the modem's FW can provide the log including debug message to describe which event/command was sent from the driver to cause the modem's FW to crash.
(b) Enable the debug in ModemManager to collect the log to know the last command sent to the modem

For Ubuntu Core, to enable the modem-manager snap:
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$ sudo snap set modem-manager debug.enable=true
$ sudo snap restart modem-manager
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