No image on clipboard

Drag and drop images to copy. However, if you look at the clipboard with the copy command, the image is not visible. As a result, the editing program does not paste.
What's going wrong all of a sudden doesn't it? Can you tell me what I'm doing wrong?

Copying from the file display copies files as files, not as images (or whatever file type they are).

Try copying from the standalone viewer.

Do you mean that the image is saved only in one state instead of dual vertically?
Is there any way to save in dual vertical?

I am afraid I misunderstood your first posting and what you are trying to do. I would need more information for an answer.

When you drag and drop an image to copy, the clipboard is not used. To have an image in the clipboard, you need to open the image in an image viewer or editor and copy it there. The image will then be in the clipboard until it is replaced with another copy or cut command.