I am migrating a sharepoint solution from Sharepoint 2010 to 2013, and so far everything works, but I'm stuck at one specific problem. In some lists, the user has the possibility to open an editor for a list item. This opens a modal dialog with some inputfields and some buttons. The masterpage is not shown in these dialogs, but that is how it's supposed to be, so no problem so far. There is however one aspx page that contains more than one asp panel, and in this modal dialog the master page layout is visible. I am not allowed to post any of my code but the general structure of these layout pages is:
A Redirect.aspx page with:
<frameset>
<Frame></Frame>
</frameset>
Where another aspx page is loaded in. This aspx page is mostly a Panel with a table in it.
I don't expect anyone to solve my specific problem, but I'm out of ideas where to look for the issue.
I am using the default master page by the way, so I added no custom code to the masterpage.