I was using my friend's EHX Small Clone chorus pedal and what I realized was there was a slight *pop* sound when I turn the pedal on or off. My friend said that that's normal on every true bypass pedal and it vanishes after 10 mins with power supply before every use.

Is this normal or we have a broken small clone?
its normal for there to be a pop on some truebypass pedals. there is a simple way to fix it if you are interested. sure it does take some modification to your pedal (just adding one part) but it is helpful. unfortunatly, i dont remember exactly what you have to do but im sure a google search should find the answer.