así que tengo 2 botones, quiero ocultar un botón cuando hago clic en él pero cuando hago clic en otro botón quiero mostrar el primer botón nuevamente
<a onClick = "this.style.visibility= 'hidden';" class='blantershow-chat' href='javascript:void' title='Show Chat'><svg width="40" viewBox="0 0 24 24"><defs/><path fill="#eceff1" d="M20.5 3.4A12.1 12.1 0 0012 0 12 12 0 001.7 17.8L0 24l6.3-1.7c2.8 1.5 5 1.4 5.8 1.5a12 12 0 008.4-20.3z"/><path fill="#4caf50" d="M12 21.8c-3.1 0-5.2-1.6-5.4-1.6l-3.7 1 1-3.7-.3-.4A9.9 9.9 0 012.1 12a10 10 0 0117-7 9.9 9.9 0 01-7 16.9z"/><path fill="#fafafa" d="M17.5 14.3c-.3 0-1.8-.8-2-.9-.7-.2-.5 0-1.7 1.3-.1.2-.3.2-.6.1s-1.3-.5-2.4-1.5a9 9 0 01-1.7-2c-.3-.6.4-.6 1-1.7l-.1-.5-1-2.2c-.2-.6-.4-.5-.6-.5-.6 0-1 0-1.4.3-1.6 1.8-1.2 3.6.2 5.6 2.7 3.5 4.2 4.2 6.8 5 .7.3 1.4.3 1.9.2.6 0 1.7-.7 2-1.4.3-.7.3-1.3.2-1.4-.1-.2-.3-.3-.6-.4z"/></svg></a> <script src="https://cpwebassets.codepen.io/assets/common/stopExecutionOnTimeout-1b93190375e9ccc259df3a57c1abc0e64599724ae30d7ea4c6877eb615f89387.js"></script> <div id='get-number'></div><a class='close-chat' href='javascript:void'>×</a>Debe agregar una identificación y asociarla con el evento de clic.
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