Merge pull request #10962 from marmelab/doc-fix-video-type

[Doc] Fix some incorrect video types

Author: fzaninotto

docs/Features.md

@@ -257,7 +257,7 @@ Let's be realistic: Many developers focus on features first and don't have much
 React-admin provides **components that look pretty good out of the box**, so even if you don't spend time on the UI, it won't look bad (unless you try hard). React-admin uses [Material UI](https://mui.com/material-ui/getting-started/), which is a React implementation of the [Material Design](https://material.io/) guidelines, the most battle-tested design system.
 
 <video controls autoplay playsinline muted loop width="100%">
-  <source src="https://user-images.githubusercontent.com/99944/116970434-4a926480-acb8-11eb-8ce2-0602c680e45e.mp4" type="video/webm" />
+  <source src="https://user-images.githubusercontent.com/99944/116970434-4a926480-acb8-11eb-8ce2-0602c680e45e.mp4" type="video/mp4" />
   Your browser does not support the video tag.
 </video>
 

docs/Theming.md

@@ -8,7 +8,7 @@ title: "Theming"
 React-admin applications use a neutral style by default. You will probably want to customize the look and feel to match your branding, or your end users preferences. Don't worry! You can customize the look and feel of pretty much everything in react-admin.
 
 <video controls autoplay playsinline muted loop width="100%">
-  <source src="https://user-images.githubusercontent.com/99944/116970434-4a926480-acb8-11eb-8ce2-0602c680e45e.mp4" type="video/webm" />
+  <source src="https://user-images.githubusercontent.com/99944/116970434-4a926480-acb8-11eb-8ce2-0602c680e45e.mp4" type="video/mp4" />
   Your browser does not support the video tag.
 </video>