I haven't yet gotten a Mavic, but I just found a convenient way to combine the series of raw 4K video files that are created by a Phantom 4 Pro. If the Mavic does something similar, this might be useful for owners of that model. I work on a Mac and had always used Quicktime to merge files. With this approach, a few black frames are introduced at the interface between files. I never found a fix for this problem -- until now. With Shutter Encoder, it's easy to eliminate this problem fast and with no loss in quality. If you just do a merge with Shutter Encoder, the black frames will be replaced by a brief pause (curiously, there is no pause when played back with VLC, but there is a pause when played back with Quicktime or on YouTube). The pause can be eliminated by first doing an extract with Shutter Encoder and then doing a merge of those files.