SingleFile
Web Extension for saving a copy of complete web page in a single file
...Wait until the page is fully loaded. Click on the SingleFile button in the extension toolbar to save the page. You can click again on the button to cancel the action when processing a page. Open the context menu by right-clicking the SingleFile button in the extension toolbar or on the webpage. It allows you to save the current tab, the selected content, the selected frame. With auto-save active, pages are automatically saved every time after being loaded (or before being unloaded if not). Right-click on the SingleFile button and select "Manage extension" (Firefox) / "Options" (Chrome) to open the options page.