This is a consequence of disabling the selection for the TitleBar of a dialog widget in a browser that does not support the selectteart event. For this browser, they disable the "mousedown" event.
line 145: jquery.ui.dialog.js
uiDialogTitlebar.find( "*" ).add( uiDialogTitlebar ).disableSelection();
line 120: jquery.ui.core.js
disableSelection: function() { return this.bind( ( $.support.selectstart ? "selectstart" : "mousedown" ) + ".ui-disableSelection", function( event ) { event.preventDefault(); }); }, enableSelection: function() { return this.unbind( ".ui-disableSelection" ); }
so you can use enableSelection () or untie it yourself
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