SM Composer sets moz-do-not-send to True, hiding images

[Konsultor]

Built multiple websites with SeaMonkey Composer because it is simple to use. Maintaining 5 domains with Composer and having no trouble until recently when I'm adding images to html pages. In Composer I created a table and inserted an image in each cell. Most work OK after I save the .html file and upload to the server with Filezilla. Trouble is that some images, when inserted by Composer, have the advance edit setting moz-do-not-send to True by default. The visible result is that the image doesn't appear in the page when editing in Composer nor does the image appear in the page read from the website. Removing the moz-do-not-send entry with Advanced Edit doesn't work--that entry remains after I remove it and save. I've deleted images and inserted them again, erased the html and jpg files from the web site and uploaded them again, checked that the URL is relative to page location in Composer and that the images are located in the desired directories.
What am I missing? The problem page is http://flanaganphoto.com/gallery-Trains.html
Thanks in advance

[Konsultor]

Using version 2.56.13 from OpenSuse

[therube]

(No clue about such things, but I'll just note that Composer has been not been maintained for ages now.
Maybe there is a bug for the behavior you're seeing, or you could submit one - you never know.
Bugzilla.)

[frg]

It is sitll maintained but basically the least important component and not many developers left. The usual spiel.

Basically the same problem as in https://bugzilla.mozilla.org/show_bug.cgi?id=1827146

Composer editor thinks it is in mail and adds stuff for security and email composition. We discussed it internally and njsg came up with some ideas. If I find some time I will look into it too. Not too hard to fix probably just needs some peace and quiet to test.

FRG