SnapCrab is one of the Sleipnir Plug-ins which captures the webpages, and saves as PNG files. Not only this plug-in captures displayed pages, but also captures the whole webpages, or selected areas.
When you need to prepare documents or papers using webpage images, SnapCrab can help you make them very easily. Just one click, and done.
This plug-in also has a color picker function which shows color code under the mouse cursor.

*If you are using Gecko engine, you can use "capture whole desktop with cursor" and "color picker" only.

Each icon has individual way of capturing web pages.

1. Capture displayed area
2. Capture whole Web pages
3. Capture selected areas of Web page
4. Capture window with cursor
5. Capture top level window with cursor
6. Capture whole desktop
7. Capture whole desktop with cursor
8. Get color code under the cursor

With the default settings, captured images are saved on desktop.
You can also save them to a selected folder or clipboard by changing settings.