Multiple copies of the same posting/comment

This occurs when you click on a "SUBMIT" or "SAVE" button and nothing appears to be happening. Clicking again causes multiple submissions of the same content.

Most browsers show that an action (e.g. clicking on a link) is being processed by showing a spinning icon at the top of the page/tab, but this is not always obvious.

I have added a function which hides the "SUBMIT" or "SAVE" button as soon as it is clicked and shows a "Please wait..." message.