from StackOverflow - Can I set-up theme for 'view-source' in Chrome?
- goto bookmark manager.
- add new link.
- paste code into link.
- move link to your bookmarkbar.
- goto chrome://settings/searchEngines
- ADD
- fill in JS in the URL.
- set a keyword as a shortcut,
darkorjquery... - ADD
- now you can type
darkin the url bar and hit enter to use the dark keyword
- now you can type