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The inserted image appears on the diagram. Now if you transfer the project to another computer, the diagram continues displaying the image. You can also insert images that are not yet attached to the project model. Read more about Inserting images into HTML text.
Exporting back to the local file system
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In the Containment tree select an already attached file or attach a new one. How to attach a file in the Containment tree >>
Warning title Image formats You can attach images of the following formats: .gif, .jpg, .jpeg, .svg, or .png.
Drag the attached file element to the diagram pane. The image shape is created.
Warning title Image does not update Image shape is not synchronized with attached file. If you replace an image in the attached file, the image shape on the diagram pane will not update.