Note that Edge has window.chrome.app.getDetails()  (see issue 768493) so there's some reason to expect we may need to standardize window.chrome.  At the moment that seems to be the only 'chrome' API implemented outside chromium.  See http://web-confluence.appspot.com/#!/catalog?releaseKeys=%5B%22Safari_11.0_OSX_10.12.6%22,%22Chrome_61.0.3163.79_Windows_10.0%22,%22Firefox_55.0_Windows_10.0%22,%22Edge_15.15063_Windows_10.0%22%5D&releaseOptions=null&numAvailable=null&currentPage=0&gap=5&itemPerPage=15&searchKey=%22chrome%22