Can't open attachment

I’ve just begun using OO5, previously stayed with OO3 (pro). I created a new document in OO5 and dragged a pdf into it. Then I saved the document. When I double-clicked the attachment to open it in Preview, I got this message:

Is this a known problem? I looked at the release notes and didn’t see anything.

You can avoid this problem by choosing “Save as file package” in the documents inspector.

It seems that support for embedded files isn’t yet implemented completely when using the flat variant of OO5’2 new ooutline file format.


Thanks! Didn’t even know that existed.