A topic that does not only concern the mini. Do you think it is recommend to replace the propellers after a certain time, lets say 100 flight hours or so, to prevent .... just a moment ... let me google the right word in english ;-) ... a possible fatigue break (german : Ermüdungsbruch) ?

I think it would be good to replace them at certain intervals. At exactly what intervals that should be, I am not sure though. This is my first experience with a drone of this type so I'm still learning myself.

Yes, i do replace my blades now and than...
Just a good feeling to fly with new blades, better safe than sorry.

Clever?  i don`t care if it isn`t   ;-)

now and then...sometimes after each flight ah, I have found something interesting on a german "drone site" ... I translate via google :

Experts recommend that even externally undamaged propellers be replaced after about 200 flights.

This is to prevent age-related malfunctions (or breaks) that could become quite unpleasant in the air.

You should also check the propellers for damage before and after each flight.

Do not worry. Your drone will not crash in the event of a small break - but in the worst case, the drone is no longer controllable,
begins to rotate around its own axis for safety reasons and lands - this is not exactly recommended over roads, water or inhabited areas.

Thank you for reaching out to DJI Forum. I hope that our valued DJI co pilots can provide you the best information for this inquiry. For reference I will be posting an image for more details about the propellers. Thank you.