Most PDFs in my family tree work as expected - they display a 'missing image' icon (camera in a red circle with line across) when previewed but open correctly in the default viewer. However one particular file gives me the error 'Format not supported. Please choose another fie' whenever I open the Gallery tab of the individual concerned, I don't even have to try opening the .pdf.
It's not the only multi-page .pdf in my tree, but it may be the only one where the page format is set to A4 landscape. The other PDFs I've looked at so far seem fine and the problem one opens externally with no issues.
EDIT: I have the same issue with another multi-page PDF (also in landscape format)
Any suggestions please?
Paul
Linux Mint 19.1 xfce 64 bit