A fix for an incompatibility introduced with Prusa firmware 6.10.x and later
Prusa firmware v6.10.x for the XL and XL+ printers introduced an incompatibility with Octorprint. Specifically the M106/M107/M201/M203/M221 commands now want a valid tool to be specified. This is (probably) a temporary fix until the bug in the firmware is corrected, assuming it is in-fact a bug.
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