thanks for the fast answers. I'm using chrome, and win7 (64bits if that data is necesary).This flow allows me to have an sound notification of the chat page when a new message arrives. The flow that i'm using its the following:
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}\n #message { width: 68%; }\n #send_btn {\n width: 10%;\n position: absolute;\n right: 0;\n bottom: 0;\n margin: 0;\n }\n\n .content {\n width: 70%;\n margin: 0 auto;\n }\n\n input[type=\"text\"],\n input[type=\"button\"] {\n border: 0;\n color: #fff;\n }\n\n input[type=\"text\"] {\n background-color: #146EA8;\n padding: 3px 10px;\n }\n\n input[type=\"button\"] {\n background-color: #f39c12;\n border-right: 2px solid #e67e22;\n border-bottom: 2px solid #e67e22;\n min-width: 70px;\n display: inline-block;\n }\n\n input[type=\"button\"]:hover {\n background-color: #e67e22;\n border-right: 2px solid #f39c12;\n border-bottom: 2px solid #f39c12;\n cursor: pointer;\n }\n\n .system,\n .username {\n color: #aaa;\n font-style: italic;\n font-family: monospace;\n font-size: 16px;\n }\n\n @media(max-width: 1000px) {\n .content { width: 90%; }\n }\n\n @media(max-width: 780px) {\n #footer { height: 91px; }\n #chat_box { padding-bottom: 91px; }\n\n #user { width: 100%; }\n #message { width: 80%; }\n }\n\n @media(max-width: 400px) {\n #footer { height: 135px; }\n #chat_box { padding-bottom: 135px; }\n\n #message { width: 100%; }\n #send_btn {\n position: relative;\n margin-top: 3px;\n width: 100%;\n }\n }\n</style>\n","x":246,"y":500,"wires":[["6f5f113f.a7bb6"]]},{"id":"6f5f113f.a7bb6","type":"http response","z":"ef0ea01e.b1269","name":"","x":389,"y":500,"wires":[]},{"id":"346cd8b4.523688","type":"ui_text","z":"ef0ea01e.b1269","group":"69009ed0.526c78","order":0,"width":0,"height":0,"name":"","label":"text","format":"{{msg.payload}}","layout":"row-spread","x":430,"y":560,"wires":[]},{"id":"9b6a3c9a.6c126","type":"ui_text_input","z":"ef0ea01e.b1269","name":"","label":"","group":"69009ed0.526c78","order":0,"width":0,"height":0,"passthru":false,"mode":"text","delay":"0","topic":"","x":280,"y":560,"wires":[["346cd8b4.523688"]]},{"id":"4a772af.0f4ddd4","type":"inject","z":"ef0ea01e.b1269","name":"","topic":"","payload":"","payloadType":"str","repeat":"0.5","crontab":"","once":false,"x":90,"y":560,"wires":[["9b6a3c9a.6c126"]]},{"id":"69009ed0.526c78","type":"ui_group","z":"","name":"Default","tab":"d16315cd.213268","disp":true,"width":"6"},{"id":"afb63a67.34cac8","type":"websocket-listener","path":"/ws/chat","wholemsg":"false"},{"id":"d16315cd.213268","type":"ui_tab","z":"","name":"Home","icon":"dashboard"}]