And if you decide to do it yourself, I don't understand why you'd need to go through an mp4 intermediate. With ffmpeg you can trim and encode your clip to webm with a single command and a couple switches. Or if you want an easy GUI tool, there's always WebM for Gits (https://github.com/nixxquality/WebMConverter )
>And if you decide to do it yourself, I don't understand why you'd need to go through an mp4 intermediate.
Screen recording. Although I use a tool that simply records as a .webm ( https://github.com/thetarkus/WebMCam ) Most people aren't going to be installing random Github projects to meet their needs. I doubt many people even know what Github is outside of the tech niche. :P So they record with some other desktop recorder that outputs as a .gif or .mp4/.m4a and then would need to convert from there.
Also Imgur's .gifv wrapper seems to be more widely known than .webm. Which is unfortunate but is the case due to Imgur's popularity.