Custom Geometry is a Firefox add-on that allows you to resize and position the Firefox window anywhere on the desktop that you like.
You can resize a Firefox browser window to any size you want manually. To do so you only need to move the mouse cursor over one of the screen edges, click and hold down the left mouse button and drag the window to the desired format.
This is usually the best way of doing so unless you want to resize the window to exact dimensions. This is for example useful for web developers who want to test websites in certain resolutions to ensure that the content of the website is displayed correctly in that specific resolution.
The rise of mobile devices has increased demand for so-called responsive themes on websites that adapt to any screen resolution that user devices may use to display it.
Another user group that may be inclined to resize the browser window are users who want the Firefox web browser to only take up part of the screen on the computer and not all of it, for instance if they want to display other windows beside it.
Custom Geometry is an add-on for the Firefox web browser that is adding options to the browser to resize the Firefox window based on fixed parameters.
The extension adds a button to the Firefox status bar that provides left-click access to the window configured menu of the add-on. A right-click displays all window resolutions that are supported by the extension.
You can add new resolutions to the extension easily. For each new resolution you have to select a desired width and height, and if you want left and top offset values for exact screen position.
It takes one click to change to the default screen resolution and two to change to any other defined in the add-on.
Custom Geometry is available on the official Mozilla Add-ons repository. It is compatible with all recent versions of the Firefox web browser.
Custom Geometry is a handy extension for Firefox. Some development options were added to recent versions of Firefox that allow you to test sites and services by emulating various screen sizes natively.
Please note that it has been updated last in 2010 which indicates that the project is either dead or on ice at the moment.
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