Join Date: Jun 2010
Location: Chilliwack, British Columbia, Canada
Model: 1984 Interstate "Canadian"
I uploaded a small attachment on Nov. 8, bookmarked the location of the image then closed the editor without posting.
Today Nov. 10 the image/file is no longer on the server, it was there yesterday Nov. 9.
It seems that a thumbnail must be attached to a post and if it isn't it gets deleted by a filter looking for orphan files.
I've marked this solved and will change how I post images.
Advise given here is free and comes with no warranty "Caveat emptor"