jQuery blockUI dialog opens when go back in browser

[iLive]

I have a jquery dialog and when I open and close it, go to another page, and after that, go back with the browser go back button, the dialog is showed again. This is happening in Chrome and IE and not in Firefox. What can I modified of the dialog? Thanks!\[code\]<td class ="approval-img"><asp:ImageButton runat="server" CommandArgument = '<%# Eval("aux_approvalId")%>' OnClick="getApprovalID_approve" ToolTip="Approve" ImageUrl="/Images/Approve.png" /></td> protected void getApprovalID_approve(object sender, EventArgs e) { ..... string script = "OpenApprovalDialog();"; Page.ClientScript.RegisterStartupScript(typeof(Page), "", script, true); }\[/code\]These are the functions for open/close the dialog:\[code\]function OpenApprovalDialog() { $.blockUI({ message: $('#approval-form'), baseZ: 10000 }); $('#approval-form').parent().appendTo($("form:first")); return false;};$('#btnCancelApprove').click(function () { $.unblockUI(); $("#approval-form").parent().detach(); return false; });\[/code\]And the dialog that is opened:\[code\]<div id="approval-form" style="display: none; cursor: default" title="Approve"> <div class="approve-change"> <ul> <li> <p><label>Approve change: </label><label>Reason</label></p> <textarea id="txtReasonApprove" runat="server" cols="1" rows="1" class="required"></textarea><br /> </li> <li> <span> <button id="btnCancelApprove" class="blue-problem">Cancel</button> <asp:Button ID="btnApprove" runat="server" CssClass="blue-problem" Text="Approve" ToolTip = "Approve" OnClick="ApproveChange_Click"/> </span> </li></ul>\[/code\]