**Overview:** When using CSS custom properties in a text-decoration shorthand, the decoration is not rendered as the browser seems to not know what to do with the provided variable or variables, rendering the whole declaration invalid. **Steps to Reproduce:** 1) Assign a color, style, or line type to a variable and use it in a shorthand `text-decoration` value. Live example on CodePen: https://codepen.io/chriskirknielsen/pen/NWYLXpr?editors=1100 Code to reproduce: ```html <p>Red dotted underline</p> ``` ```css p { --color: red; text-decoration: underline dotted var(--color); } ``` **Actual Results:** The text-decoration is not rendered. **Expected Results:** The text decoration should render below the text, dotted and in red. **Build Date & Hardware:** Using Safari Technology preview, Release 151 (Safari 16.0, WebKit 17615.1.1.2) Running macOS Monterey 12.4 on MacBook Pro (16-inch, 2019) **Additional Builds and Platforms:** DOES OCCUR on Safari Version 15.5 (17613.2.7.1.8) on macOS Doesn't occur on Chrome Version 104 on macOS Doesn't occur on Firefox Version 103 on macOS