...Bootstrap uses certain HTML elements and CSS properties which require HTML5 doctype. Summernote uses the Open Source libraries jQuery and Bootstrap, if you are using the Boostrap 3 or 4 versions of Summernote, or just jQuery if you use the Lite version of Summernote. Summernote allows you to customize the toolbar. You can compose a toolbar with pre-shipped buttons. Air-mode give an interface without the Toolbar. To reveal popover Toolbar, select a text where you want to modify. Simply turn on airMode and just focus on text. ...