PostRequest: fixes #50889

git-svn-id: svn://svn.jdownloader.org/jdownloader/browser@26843 ebf7c1c2-ba36-0410-9fe8-c592906822b4
git-svn-id: svn://svn.jdownloader.org/jdownloader/browser@26844 ebf7c1c2-ba36-0410-9fe8-c592906822b4
git-svn-id: svn://svn.jdownloader.org/jdownloader/browser@26845 ebf7c1c2-ba36-0410-9fe8-c592906822b4