Hello Binnette! First of all, thank you a lot for useful and convenient tool!

My team working on protection of central Russian nature against of invasive plant Heracleum Sosnovsky Manden and using UMap service for problem demonstrating and works planning: http://umap.openstreetmap.fr/ru/map/map_424586#6/57.636/38.511

We have some questions about functionality, but most important question, does the OSM service have any limitations on objects number and which number of polygons could degrade the map performance noticeable ( 1K, 1M, 1B :) )? Currently we only at the beginning, but potentially we could need support of several millions polygons, is it OK?

Thanks and best regards, Maria Popova