Tested with: https://jsfiddle.net/xpvt214o/160079/
method browser key which keyCode charCode
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keydown Chrome l 76 76 0
keydown Chrome numpad enter 13 13 0
keydown Firefox l 76 76 0
keydown Firefox numpad enter 13 13 0
keydown IE l 76 76 0
keydown IE numpad enter 13 13 0
keypress Chrome l 108 108 108
keypress Chrome numpad enter 13 13 13
keypress Firefox l 108 0 108
keypress Firefox numpad enter 13 13 0
keypress IE l 108 108 108
keypress IE numpad enter 13 13 13
Chrome = Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.181 Safari/537.36 Firefox = Mozilla/5.0 (X11; Linux x86_64; rv:59.0) Gecko/20100101 Firefox/59.0 IE = Mozilla/5.0 (Windows NT 10.0; WOW64; Trident/7.0; .NET4.0C; .NET4.0E; .NET CLR 2.0.50727; .NET CLR 3.0.30729; .NET CLR 3.5.30729; wbx 1.0.0; rv:11.0) like Gecko