Use of window.showModalDialog() is deprecated. Use window.open() instead. For more help https://developer.mozilla.org/en-US/docs/Web/API/Window.open
Ужыванне window.showModalDialog() асуджана. Скарыстайце window.open() замест. Больш падрабязныя звесткі на https://developer.mozilla.org/en-US/docs/Web/API/Window.open