This plugin allows you to embed widget areas via shortcode. You can add them to your pages and posts. This can be useful for embedding scripts like opt-in boxes, which often do not work when inserted directly into pages and posts.
You can also use this plugin for variable content which needs to appear the same on many pages, such as a call to action. You can put that content in a widget, and embed that widget into the necessary pages via the Widgets on Pages shortcode. Then, when you need to change the content, you only have to do so in the widget, instead of editing all of your pages.
- Go to the Settings > Widgets on Pages menu. Create a new widget area for the code you want to paste into your post/page. Give it a name you can use to easily identify later.
- Go to the Appearance > Widgets menu, add a plain text widget to that widget area, and paste the code into that plain text widget.
- Note the shortcode for that widget (you can see this inside the widget area). It is in the format [widgets_on_pages id=”Example Widget Area”].
- Paste that widget’s shortcode in your post/page.
More information: https://wordpress.org/plugins/widgets-on-pages/