Indesign 2018 not saving image previews with document

[lowy]

I'm sharing an indesign 2018 (13.1) file with a client over dropbox.

When I save the file with all images linked and accounted for, it looks fine at my end.

When saving I ensure that "Always save preview images with documents" is checked.

In the past (pre-2018), even if the links were not available, I would still see the images in low res preview mode. Now I just see grey boxes. Is this a  problem anyone else is experiencing?

Please tell me this hasn't been done on purpose by Adobe....

I'm on a Mac - MacBook Pro (Retina, 15-inch, Early 2013)

If I look at the file from another site, on a 27" iMac same problem occurs.

Client I'm working with is on a PC. Don't know what spec.

Any help appreciated.

[Dave Creamer of IDEAS]

The "Always save preview images with documents" is for the InDesign document preview, usually for Bridge.

Are you sure you are not in View>Display Performance>Fast Display mode? Sometimes it happens by accident with a keyboard command.

[lowy]

Positive. Checked numerous times. Once the file is opened on the other computers the file size also drops by 60%, so it looks like its losing the preview information somehow because it can’t find the original links. Never used to do that.