One of your suggestions led to the solution with a difference of one small detail.
A very long Scan To destination folder name was causing the problem. The language, English, remained the same.
I think, the manufacturer, as you suggested, as part of the issue, probably truncated the allowance of title characters, in the software, possibly thinking nobody would use something that long, which, if true, is silly to me, since the OS allows 255 characters in a title, and, a programmer would write in the 255 maximum character limit, to avoid compatibility problems, with the OS Image Capture is integrated into. Is common sense dead or is there another explanation?
Also, personally, I'm not a fan of changing the widths of several columns at one time, when extending one side of a user window, without a choice of being able to only affect one column. They have this versatility in Finder but not in the user window of Image Capture in the same OS? There's no user consistency.
The whole mindset, that I'm seeing, at this time, brings up questions as to their approach in programming for a user friendly interface that runs smoothly. Things don't consistently behave, in the visual manipulation, and I suspect in other areas of use across the board.
This is what I did, with your help, to fix the Image Capture use window issue.
-Shut down, reboot in Safe Mode.
-Opened Image Capture. Details section still extended to the right.
-Details Section at the Scan To line - Single change of shortening a very long title in that list. (The extension to the right was about the length of the long title).
-Quit Image Capture to refresh, for the heck of it.
-User window went back to normal.
-Restart computer
-Image Capture user window back to normal.
Although I was not in a different language, I had added a new, very long folder name to the list of Scan To locations. The widening of the Details column, as in the picture, is as long as that long title. The widening didn't happen in front of my eyes however. I diverted my gaze to do something else, then visually went back to the Image Capture user window, where upon the right side was grossly extended. There was a delay in the extension happening.
P.S Lol point made when I copy pasted this reply from a Pages document to here. Several spacing lines were automatically omitted. But, when I copy pasted this back onto the Pages document, the spacing was preserved. Now, this is in a totally native environment. This is the OS creator's webpage and application. The consistency isn't there.