QuickScripts ：Allows the user to create a set of quick text replacements so you can automatically insert frequently used text based on text keys. Once you've created your text and keys just type the key in any text box and hit Ctrl+. and your text will be entered...
Updated QuickScripts to work with input fields inside of an iframe
Once you have installed the QuickScripts go to the Add-ons section in Firefox and then go to the options for QuickScripts. Once you’re on this page you will need to add a key and text pair.