Recording a video with transparent background:
Preparing the video in AfterEffects:
Installing webm plugin for Adobe:
Close all Adobe Programs.
Visit this page and download the plugin:
[Disclaimer: Also we have made good experiences with this plugin, we can not provide any support or warranty for third party software. Use on your own risk! Thanks to fnordware.com for creating this plugin!]
Install it by executing WebM_Premiere_v1.1.0.msi
Start Adobe Media Encoder: The new file format should now be available.
Rendering the video with correct export settings in Adobe Media Encoder: