FullScreen Search is a lightweight plugin which can be used to add full screen functionality. The plugin doesn’t affect the speed and performance of site. It is 3kb in size. Also, you don’t have to do settings to make this plugin.
You just need to install this and activate the plugin. The plugin will work in background and you don’t have to do any settings.
You can live example on our website. Just move the cursor towards header and click the search icon.