Various editor fixes (#160)

* Tab should move to body from heading

* Focus editor on mount, closes #156

* Closes #154 - Just went for the simple approach here, considered something more complex but this is clear

* Added body placeholder

frontend/components/Editor/plugins/MarkdownShortcuts.js

@@ -20,6 +20,8 @@ export default function MarkdownShortcuts() {
           return this.onDash(ev, state);
         case '`':
           return this.onBacktick(ev, state);
+        case 'tab':
+          return this.onTab(ev, state);
         case 'space':
           return this.onSpace(ev, state);
         case 'backspace':
@@ -184,6 +186,17 @@ export default function MarkdownShortcuts() {
       }
     },
 
+    /**
+     * On tab, if at the end of the heading jump to the main body content
+     * as if it is another input field (act the same as enter).
+     */
+    onTab(ev: SyntheticEvent, state: Object) {
+      if (state.startBlock.type === 'heading1') {
+        ev.preventDefault();
+        return state.transform().splitBlock().setBlock('paragraph').apply();
+      }
+    },
+
     /**
      * On return, if at the end of a node type that should not be extended,
      * create a new paragraph below it.