Marco Godoy

Just my two cents: mp4 is a container format, so you need to know the codecs inside (normally h264 + aac). Playback depends on having the right codecs, and Ubuntu...

This issue is not related the the one fixed in 5.0.2. I think the solution for this case is to use [enforceExtension](https://webpack.js.org/configuration/resolve/#resolveenforceextension) instead of using `fullySpecified` [here](https://github.com/AnomalyInnovations/serverless-bundle/blob/3e59331faac6e7af8b095ed8a8ac3db082a42785/src/webpack.config.js#L200)

After some more digging, it seams that `fullySpecified` was added [here](https://github.com/webpack/webpack/commit/205bbb4c0d181c6770108c3d8b5e1818867776e3) on July 17 (and can't see exactly which version does have it for the first time). Maybe updating webpack...

PR for this feature created as #7 Please let me know if it's ok.