Administrators are able to maintain the list of pages which do not display the watermark.
Click “Pages without watermark“ and select pages in the dialog to hide its watermark.
Note:
If a page does not display watermark, the watermark will also not be displayed in attachment preview even if "Show Watermark in Attachment Preview" is turned on.
Whether the exported word / PDF has a watermark is not affected by whether the watermark is displayed on the page.