pros:
- Everything is processed locally, nothing is sent to the cloud. This means privacy, but also speed: if you want to extract a 20 seconds part of a 800 MB video file, you don't have to wait for the upload. - No limits on frame size or video length. It isn't using any cloud resources so no need to put artificial limits on that. - Precise timing. Seems like a small thing, but surprisingly difficult to get it right with html <video> tags. - Preview matches exactly the final result: the exact same code generates the preview and the exported video, not some ugly hack attempting to replicate what you see in the browser to the cloud renderer.
cons:
- It only works properly in Chrome and Edge, with some acceptable fallbacks in Firefox. - HEVC is not supported by any browser, so for that FFmpeg is needed but that's only fast enough on recent computers - Everything needs to be loaded into memory. Compared to the cloud-based editors this isn't much of an issue as those typically limit you to 100-200 MB files anyway, but eventually I'd like to use the Filesystem API to make it possible to edit videos of any size.
Also there are plenty of more advanced features: unlimited number of layers, motion tracking, blending modes, using LUT files, a not-so-basic painting tool, etc.
Let me know if you have any questions or feedback!
mp3 files not loading was an embarrassing bug, I just fixed it, should work now. (only remaining issue I just realised is that the volume panel doesn't show up when the track is first selected, I'll look into that later)
I suspect that the drag and drop limit of 5 may be a browser/OS limitation, now I couldn't reproduce this but will look out for it. And yes, probably it would make more sense to put them on the same track after each other so I will change that. Thanks for pointing this out!
Also as the preview playback is done with html video elements and those can't be started at a precise enough time, the timing of these videos are imprecise and may not align with other elements. This only happens at playback or scrubbing, not when staying on a single frame and the exported result should not be affected.