'Light rail (or light rail transit, abbreviated to LRT) is a form of passenger urban rail transit that uses rolling stock derived from tram technology while also having some features from heavy rapid transit.' - Wikipedia
Plenty of cities have light rail lines that are used by trams. For examples marked as such on OSM, see Köln, Dortmund, Essen, Duisberg, Northeastern Paris, or any number of other cities with mixed systems. Also, regarding your claim that 'reverting… is not allowed', please bear this in mind next time you revert a change, so as to avoid hypocrisy.