let start = document.getElementById('btn_start'); let stop = document.getElementById('btn_stop'); start.onclick = function() { browser.windows.update(browser.windows.WINDOW_ID_CURRENT,{state:"fullscreen"}); console.log("test start!!!!"); }; stop.onclick = function() { browser.windows.update(browser.windows.WINDOW_ID_CURRENT,{state:"normal"}); console.log("test stop!!!!"); };