slightly OT what are the price on which a stop loss should trigger off? "executed" price or market price?

I'm asking because if the latter is valid then all that was needed to trigg the stop loss order is for the highest bid to suddenly drop, even if there was no actual trade related to this dip. So there might have been a flash crash in the bid even though there was no flash crash in executed price.

Since if the makerket is still pretty low volume and has stop loss order based on market price, the highest bid can easily move a lot, especially on a volatile period like the ones we're in.