Attachments in the HTML editor are saved in the activity stream even when the image is not actually saved in the knowledge article.
Go to kb_knowledge_list.do and open a knowledge article that is in Draft state.
Configure activities on the form using for layout.
Go to html editor and copy paste an image in it.
Reload the form.
Note that the image was saved to the record and is visible in the activity stream even though it was not actually saved.
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