There is a GFVS backend /usr/lib/gvfs/gvfsd-archive which can mount images along with archives. You can use it. Nautilus has application shortcut shipped for it so if it is installed 'Archive Mounter' will be present in your right-click menu on any disk image. If you don't have such application shortcut you can just borrow one from any Nautilus package.
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There is a GFVS backend /usr/lib/gvfs/gvfsd-archive which can mount images along with archives. You can use it. Nautilus has application shortcut shipped for it so if it is installed 'Archive Mounter' will be present in your right-click menu on any disk image. If you don't have such application shortcut you can just borrow one from any Nautilus package.