... I don't remember something specific to images. But I do remember that the table setting issue was caused by a legacy margin setting, which slowly expanded the table.

I'm guessing it could be a paragraph setting from an earlier version of Notes, that isn't being interpreted "well" by the later version.

Blake,  Have you had any luck resolving or isolating this? 

I am seeing the same thing.  I have been able to re-create the problem, when I copy and paste the attachment from one location to another and then delete some text above (closer to the top of the document) than the rich text field. Copied icons stretch.  However, an icon created using File - Attach, do not seem to stretch.

The copied icons stretch if I use Ctrl+s to save the document or if I use the Save button containing @Command([FileSave]).  Do you think it has to do with refreshing the screen or document?  Must rich text fields be saved with a lotus script Doc.Save or UIdoc.Save?

PMR resolved for the issue: 65002,442,000 - attachments' icons getting stretched after exiting "edit mode"

Solution: Disable (remove tick) the application property "Display Images after Loading"