Colour variation tool
Swatches lets you quickly grab variations of any hexadecimal or RGB colour you enter, and then quickly copy any shade to the clipboard with the click of a button.
Get it on AppCenter
Get Swatches and more on elementary AppCenter, the open, pay-what-you-want app store for indie developers. Every app is open source and has been reviewed and curated by elementary to ensure a native, privacy-respecting, and secure experience.
Note: This app is only available for elementary OS Loki. If you’re on elementary OS Juno, it will not appear in AppCenter.
You can reach out to the developer and ask that they update it for Juno.