What did I do?

Update MCEF binding to JCEF 78.3.9

H.264 support? Play Bilibili Video?

Because of issues of license, Chromium project does not provide official *.dlls which support h264.

1. Build JCEF

   https://bitbucket.org/chromiumembedded/java-cef/wiki/BranchesAndBuilding

2. Replace the (J)CEF DLLs.

   copy files in jcef_build\native\Release to your MC folder.

3. Build CEF (you can enable ffmpeg to support h264)

   https://bitbucket.org/chromiumembedded/cef/wiki/BranchesAndBuilding

   or download compiled h264 CEF here

   https://blog.csdn.net/epubcn/article/details/82689929 (The uploader is not me, I just google and find it)

4. Replace the (J)CEF DLLs.

   copy CEF DLLs to your MC folder and replace existing files

5. Enjoy the amazing mod