I'm gonna jump in here with a "same here". I've been able to upload animated maps, webm to be specific, here and there, but I'm always met with either engorged "upload" times or it just doesn't upload at all and I get no notification. This morning, I tried again. First, I uploaded two animated tokens, each a little less than 2mb. They took longer to upload than I would have liked, but they appeared in my list and I was able to use them Then I tried to upload an animated map. The map's dimensions are large - 2048x1810 - but the file size is 4.7mb. I cleared the console of my browser's dev tools and dropped the file onto the upload area. This is what I get: Uncaught abort("Cannot enlarge memory arrays. Either (1) compile with -s TOTAL_MEMORY=X with X higher than the current value 268435456, (2) compile with -s ALLOW_MEMORY_GROWTH=1 which allows increasing the size at runtime but prevents some optimizations, (3) set Module.TOTAL_MEMORY to a higher value before the program runs, or (4) if you want malloc to return NULL (0) instead of this abort, compile with -s ABORTING_MALLOC=0 "). Build with -s ASSERTIONS=1 for more info. A quick google search suggests that this isn't necessarily a problem with the size of the file being uploaded, but that the ffmpeg buffer server side should be increased to 536870912 in order to accommodate larger dimensions. I tried uploading as MP4, first with 8mbps then with 4mbps to get a 4.6mb file and a 2.2mb file respectively. Notably, both immediately seemed to fail, with the same error in the console, but after refreshing the page, the MP4s both appeared in my library, now as WEBM files. EDIT: Even though both now appear in my library, dragging either of them to the playfield results in a slew of additional errors in the console, but no map on the screen. Similarly, I get console errors when mousing over the icons in the library - 403 Forbidden and "Error loading graphic, probably due to CORS" whatever that is.