HTML and CSS Reference
If you try to use the formatting toolbar to style the contents of the visual editor, you'll notice
that none of these buttons work. Don't fret; you'll fix that in the next section.
After you've made changes, try closing the window. You should see a warning message
Figure 3.3. The isDirty variable we created earlier allows the application to keep track of whether the user has
made changes to the document. If they've made changes and try to close the window without saving, they'll be
shown this warning message to confirm they want to leave the page.
Because the saving function hasn't been implemented yet, you can ignore this warning and
leave the page. You'll add the saving function in a later section.
Now that you have the basic visual and HTML editors working, let's move on and add
some formatting functions to those do-nothing toolbar buttons.