Design Mode puts your Chrome browser into edit mode so you can make changes to pages without reloading the page. You can make changes to individual pages, or to the whole document, such as making the body text a different color. You can also add a background image to the page, or make a number of other changes to individual pages. You can make text longer or shorter, change its color, or move it around the page.

There are some things to consider when using this feature, however:

Design Mode does not work on all pages; for example, it does not work in frames or iframes.

You can make changes to your current document, but it will not change the state of other pages in the current document.

Your changes will only last for as long as you keep Chrome in edit mode. If you change the document or close Chrome, then the changes will be lost.

You can only edit an individual page at a time.

If you save a new version of the page, then that version will replace the current version.