New flight mode does not show up in Mission Planner

Hey guys, as is shown in the title, I add a new flight mode for plane in APM, following the steps in https://ardupilot.org/dev/docs/apmcopter-adding-a-new-flight-mode.html, and compile successfully in a virtual machine with Ubuntu18.04, and open the Mission Planner in the physical machine(Windows). But the new mode does not show up in MP. I tried the method adding the new mode’s name to ParameterMetaDataBackup.xml and I have comitted the code to the master using git commit -m '...', but it still doesn’t work. It will be very grateful if anyone could help with it, thanks.