Forward/reply button missing in gmail

Have you received an email and would like to forward it or reply to it but the Forward/Reply button is missing?

This happens because an image or line of text is making the message too large to display correctly and the button is being pushed out of frame.

To get the button back, click the More menu button in Google Chrome 

then use the ZOOM controls to decrease (- ) the size of the message till the button reappears.