TINY-3917: Added docs for the new placeholder setting

_data/nav.yml

@@ -102,6 +102,7 @@
     - url: "#min_height"
     - url: "#min_width"
     - url: "#mobile"
+    - url: "#placeholder"
     - url: "#preview_styles"
     - url: "#quickbars_image_toolbar"
     - url: "#quickbars_insert_toolbar"

_includes/configuration/placeholder.md

@@ -0,0 +1,16 @@
+## placeholder
+
+This option adds placeholder content that will be shown when the editor is empty.
+
+Alternatively, the `placeholder` attribute on the original DOM element can be used instead, if the placeholder setting isn't specified.
+
+**Type:** `String`
+
+##### Example
+
+```js
+tinymce.init({
+  selector: 'textarea',  // change this value according to your HTML
+  placeholder: 'Type here...'
+});
+```

configure/editor-appearance.md

@@ -50,6 +50,8 @@ description: Configure the editor's appearance, including menu and toolbar contr
 
 {% include configuration/mobile.md %}
 
+{% include configuration/placeholder.md %}
+
 {% include configuration/preview-styles.md %}
 
 {% include configuration/image-toolbar.md %}