Add vscode-browser-preview

## Name of the extension you are adding

Browser Preview for VS Code 

## Why do you think this extension is awesome?

A real browser preview inside your editor that you can debug.
Especially useful when developing on just one screen, so you don't have to switch back and forth between open windows all the time

## Make sure that:

<!-- 
Check off the checkboxes with an 'x' like this: [x] 
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- [x] Screenshot/GIF included (to demonstrate the plugin functionality)

- [x] ToC updated

README.md

@@ -111,6 +111,7 @@ A curated list of delightful [Visual Studio Code](https://code.visualstudio.com/
   - [Seti-UI](#seti-icons)
   - [Material-Icon-Theme](#material-icon-theme)
 - [Uncategorized](#uncategorized)
+  - [Browser Preview](#browser-preview)
   - [Carbon-now-sh](#carbon-now-sh)
   - [Code Runner](#code-runner)
   - [Color Highlight](#color-highlight)
@@ -766,6 +767,12 @@ To enable Emmet support in .twig files, you'll need to have the following in you
 
 # Uncategorized
 
+## [Browser Preview](https://marketplace.visualstudio.com/items?itemName=auchenberg.vscode-browser-preview)
+
+> Browser Preview for VS Code enables you to open a real browser preview inside your editor that you can debug. Browser Preview is powered by Chrome Headless, and works by starting a headless Chrome instance in a new process. This enables a secure way to render web content inside VS Code, and enables interesting features such as in-editor debugging and more!
+
+![Browser Preview Demo](https://raw.githubusercontent.com/auchenberg/vscode-browser-preview/master/resources/demo.gif)
+
 ## [Code Runner](https://marketplace.visualstudio.com/items?itemName=formulahendry.code-runner)
 
 > Run code snippet or code file for multiple languages: C, C++, Java, JavaScript, PHP, Python, Perl, Ruby, Go, Lua, Groovy, PowerShell, BAT/CMD, BASH/SH, F# Script, C# Script, VBScript, TypeScript, CoffeeScript, Scala, Swift, Julia, Crystal, OCaml Script