Screen Draw, a Firefox add-on, lets you draw or type over any webpage in any color or size and save it in PNG and JPG format. Besides just for fun, it can be quite handy for people who want to draw arrows, circles or add text to emphasize text, images or diagrams on a webpage.
Once you’ve installed the add-on, you will find a Screen Draw button in the add-on bar at the bottom of the screen. Click this button to toggle Screen Draw On/Off. When you click the button, a toolbar pops up which lets you draw and add text on top of any webpage. Click the text or brush button to draw or add text and move the slider to increase or decrease the brush or font size. To change which color the extension draws or types in, click the color box on the add-on’s toolbar and select a color from the color grid that pops up. You can use the eraser to remove parts of your drawing or text. Once done, save the entire webpage or the visible part, select an option and the screenshot will be saved to the local system.
Move your mouse around to draw any where on the page, change colors and add text using the controls.
The Screen Draw Preferences allow you to change the default color and brush size. Additionally, you can choose to set the default capture mode foe the extension i.e., full page or just the visible part of the webpage. Select either Visible Area or Full Page from the Save mode dropdown.
The options let you choose font family and set the font size according to your preferences.
Screen Draw is a user friendly add-on and can easily be used to annotate any webpage. You can install the add-on from the link below.