Just found a new addon called Ready to Fly Button Skipper on Flightsim.to which allows any flight to start automatically without the need of mouse-clicking the “READY TO FLY” button.

What’s more, the trigger time can be shortened or lengthened by altering the value as shown in the highlighted script in the MissionStartup.html of the addon.

The default value of 3000 equals to a 3-second trigger. I find 1000 (or 1-second) better suits my needs, especially in scenarios like activities where landing challenges should be started as soon as possible.

Thanks hawkeyesk for giving us such great handiness.