Lots of websites have forms on them where you enter various details. For a quick way to fill out website forms, check out the InFormEnter add-on. That extension adds small icons next to input fields which you can click on to fill out forms with.
This is the InFormEnter page on the Mozilla website  from which you can add the extension to Firefox. Then open a website page with a form on it or one that includes username and password text boxes. You’ll find the fields now include a small arrow button beside them as shown below.
First, enter form details such as address, email, etc into the InFormEnter Options window. Press Open Menu > Add-ons and press Options beside the InFormEnter add-on to open the window below. Enter your details on the Profiles management tab below.
Open a page with a form on it and press the buttons beside the fields to open the menu below. It includes all the details you entered in the Profiles management tab. Now you can select the pertinent field details from there to enter them into the form.
To enter user name and password details with this add-on, you can set up alternative profiles. Click the Add button on the Profiles management tab to set up a new profile for another website. Then you can select passwords from alternative profiles.
So with this add-on you can now quickly fill out website form fields by pressing buttons. You can find further details at the InFormEnter website .