Firefox and Chrome seem to give different results with
window.getSelection().toString() especially in conjunction with the
encodeURI() method. Select any of the "non-break space" in bold below to get an alert with the string and its encoded counterpart.
non-breaking space? Let's try UTF non-breaking space in decimal or non-breaking space in hex?
Bug report on Firefox
%20: Firefox 50.1.0 on Ubuntu, IE 11.576.14373.0 on Windows 10, Microsoft Edge 38.14393.0.0 Microsoft EdgeHTML 14.14393 on Windows 10, Firefox 50.0.2 on Windows 10,
%C2%A0: Chrome 55.0.2883.87 on Ubuntu, Google Chrome 55.0.2883.87 m on Windows 10, Opera 41.0.2353.69 on Windows 10,