[GuidoK]

So I was wondering about Max' pitstop during the yellow flag of DEV.

Isn't that a strategic risk?
I mean there might be an advantage as under yellow it's safe to assume that cars drive a little bit more slowly (at the place of the accident), and when coming in for tyres would result in less time lost, but that only applies when the accident happened within ~20sec of the entry of the pitlane. In this case DEV crashed in turn 6 which is probably more than a minute away, so there you gain nothing.
And on the other hand, a yellow flag means in incident and can always turn in to a VSC/SC situation (which it also did in this instance) which would mean coming in during yellow would mean a substantial risk to miss out on a 'free' pitstop.

So taking that into account, it would virtually always mean a strategic risk to pit during yellow flag, unless yellow is within ~2-3 corners from the pitlane.