When I open a file created to Photoshop 2020 'export layers to files psd or tiff format, I do not see the correct image in Designer or Photo (version 1.8.3.641), yet if I open the same file in DXO Photo I see the correct results.
Also, if I drag a number of pdf files as layers I do not see anything, but if I open the file individually I see the 'correct' image.
_0004_red tie.pdf
0003_pink tie.pdf