what is mode:shim actually doing?

Question

what does mode:shim do?

i searched this site for a method of forcing flash. the code developer wrote this answer to a question from someone having the exact problem i am facing:

MediaElement.js - force Chrome to use flash player?

my observation is that modern browsers load an html5 component, then switch to flash, but very confusing on its actual behavior.

Answer 1

As you said, it will force the flash fallback. in case of modern browsers, the init of html5 video will be overruled by the flash fallback.

// allows testing on HTML5, flash, silverlight
// auto: attempts to detect what the browser can do
// auto_plugin: prefer plugins and then attempt native HTML5
// native: forces HTML5 playback
// shim: disallows HTML5, will attempt either Flash or Silverlight
// none: forces fallback view