Lost .jpg thumbnails

[John Lagrue]

Some time over the last month of so my Gnome desktop has lost the ability to
generate thumbnails of jpgs.

I have all the options set; the maximum filesize for thumbnails is set to
10Mb, so that's not the issue. Bmp, gif and png files all show as thumbnails
in Nautilus - but no jpgs do.

Does anyone have an idea of what might have gone wrong?

JDL