Learn how to send, copy, and drag images from Image Viewer to other apps. Sending Images To Other Apps
"Open With…" Action

Click the Open With… menu item. A dialog with a list of applications will appear.

Select the application you want to open the image with.
Copy & Paste

Click the Copy to Clipboard (edit-copy-symbolic) button. A toast notifying you that the image is in your clipboard will appear.

Paste your image in your application of choice.
Drag & Drop

Zoom out from the image completely.

Click and hold the selected image.

Drag the image to your application of choice.