Read&Write for Google Chrome web toolbar won’t open on a website

If you click on the purple puzzle piece icon to open the Read&Write for Google Chrome web toolbar and it doesn't open on a web page:

Read&Write for Google Chrome Web Toolbar Icon  

The webpage may be using frames which aren't currently supported for Read&Write for Google Chrome

To check if a webpage uses frames in Chrome, right click anywhere on the page and you’ll see the following menu appear

Website with Frames


The menu appears as below on a page without frames

Website without Frames