Whether it be in the fall with the leaves that fly off or in winter after a big blizzard, each tenant has to clean his balcony.
However, it must be remembered that the tenants of a building all live together and must accept the minor inconveniences of the common life.
That is to say that when you swipe your balcony there may be some dust or leaves falling on the lower balcony. But if the tenant below intentionally throws his snow on the balcony below then he disturbs the peaceful enjoyment of the premises.
Similarly, an occupant of an upper floor who, instead of bringing down his garbage bags, prefers to throw his bags down the balcony and then carry them into the container, will disturb the tenants on the ground floor, in addition to the risk of attracting vermin if the bags do not stand up to the fall.
If you find that your tolerance level has been reached, start talking with your neighbour. Perhaps he does not realize that he bothers you. Sometimes a simple explanation or a good discussion solves many conflicts. If nothing changes, contact your landlord, he can support you in your requests.
Finally, tolerance is necessary, but we must integrate in our relations with the other occupants of the building a behaviour which is acceptable for all.
Reminder: This winter, remove the snow from the surface of your balcony, it is for reasons of safety of the occupants in case of fire. The firemen from the fire protection service should have access to the balcony and the gateway to the privative portion in case of intervention. In addition, the residents must have access to the balconies in case of fire, which could be difficult when they are full of snow.