Update README.md

Author: Liooo

README.md

@@ -1,2 +1,30 @@
-# github-comment-draft
-github-comment-draft
+# Github Comment Draft
+
+Automatically saves/restores your draft comments on Github. 
+
+[Chrome web store](https://chrome.google.com/webstore/detail/github-comment-draft/nckohkpmnocinomefhgnofbicepplojh)
+
+![githubcommentdraft-demo](https://user-images.githubusercontent.com/1630378/44530470-68e2ec80-a729-11e8-8164-b443bfc79591.gif)
+
+Originated from https://github.com/isaacs/github/issues/376
+
+-----------------
+
+What this plugin does
+
+1. saves every single input in textareas into `localStorage`
+2. restores the saved draft if the focused textarea is empty
+3. removes the draft on form submit
+
+The darker blue border color around the focused text area (see the gif above) indicates that the plugin is working on the field.
+
+If you wanna clear the saved drafts manually, just do it  by yourself.
+In develper console,
+
+```
+for(let i=0;i<localStorage.length;i++) {
+  localStorage.key(i).indexOf('github-comment-draft') === 0 && localStorage.removeItem(localStorage.key(i))
+}
+```
+
+__Caveat: This plugin takes care of input in `<textarea />` only. It won't cover the github built in editors like https://github.com/Liooo/github-comment-draft/edit/master/README.md__