^^ what msinger said (22mph = 35km/h)
For the most part the AC will hold steady enough to capture most still pictures in low-moderate winds.
Personally I wouldn't fly when wind gusts exceed 40km/h myself. That then leans to an average windspeed being around the 30-35km/h range or less.
But I have a Mavic Air, and it's footprint is somewhat smaller than the fully fledged Mavic, of which by design should be more stable in-flight than the smaller Air.
If you're talking safety in regards to ensuring your Mavic can get back home to you, I'd be generalising the advertised top speed of the Mavic then take 20-30km/h off that to ensure it can overcome a headwind to return home.
Also in those circumstances allow plenty of battery to be consumed battling headwinds etc. Eg, if you used 50% out with a tailwind, the last 50% won't get your AC back home. That also depends on the distance required to be recovered to return home too etc..
Reducing altitude for the return home may save you too, being in the lower wind profile were it is slower closer to the ground.
A lot of factors to determine what is "safe", depending on the situation/circumstances.