After a print abort, a "M84" is sent to the printer. This will cause all stepper motors to be shut off, which may cause the toolhead to fall on Z belt machines. For compatibility with Mini 2 and Quiver, a "M18 X Y" should be used instead.
Also, Cura will send a "M104 S0", but it does nothing to shut off the second toolhead. Recommend sending "M104 S0 T0" followed by "M104 S0 T1" to ensure both hotends are turned off (the second command will be ignored if the FW only supports one toolhead).
These relevant code that needs to be changed is this.