I saw some research that suggested planes (and cinemas) don't transmit the virus as much as a bar or restaurant, say, because you aren't really aerosolising the virus in the same way (i.e. vigorous conversations). Apparently the worst places are things like choirs and church where everyone is spraying potential virus into the air...

Do we really have any definitive answers around masking effectiveness in different situations, there must have been some decent research by now?