There are droplets you can see, and droplets you can sometimes see (like steam, or your breath on a cold day) and aerosol "droplets" far too small to see, all of which can be exhaled from your lungs.
Most large and medium size droplets will fall to the ground fairly quickly, and not travel in the air very far (6 feet or less).
Aerosols, especially the very small ones, tend to float in the air for a considerably longer time, and not fall at all. They might gradually evaporate and get even smaller and hang around quite a while.
From post #47 above "CDC tells you that the SARS-CV-2 virus is approximately 0.125 um in size."
Although masks generally filter out larger droplets just fine, the aerosol droplet that may contain this virus can be less than 1 um in size, far too small to be stopped by any standard masks generally available to the public.
Grandpa Drudge, just to add to your excellent post, Aerosols that float around in the air will get sucked right around the edges of any unsealed mask.
Unless the mask is fitted and checked for seal, it will allow unfiltered air into your lungs. And it doesn’t take much of a leak to allow most of the air inhaled to come through the leak. Air will move through the path of least resistance. And the mass of an aerosol droplet is so small, it will travel with the easiest air current.
Who determines that the virus is contained in 1 um aerosols? If they are in that size, I would expect they would evaporate almost instantly. When the outer coating of water vapor goes, so does the virus.