backport PR 1586

docs/pages/resources/changelog.md

@@ -22,6 +22,7 @@ New versions of Web Awesome are released as-needed and generally occur when a cr
 ## Next
 
 - Fixed a bug [in the localize dependency](https://github.com/shoelace-style/localize/issues/20) that caused underscores in language codes to throw a `RangeError`
+- Fixed a bug in `<sl-copy-button>` that prevented exported tooltip parts from being styled [#1586]
 - Updated `@shoelace-style/localize` to 3.1.0
 
 ## 2.9.0

src/components/copy-button/copy-button.component.ts

@@ -206,9 +206,9 @@ export default class WaCopyButton extends WebAwesomeElement {
         ?disabled=${this.disabled}
         ?hoist=${this.hoist}
         exportparts="
-          base:tooltip__base
-          base__popup:tooltip__base__popup
-          base__arrow:tooltip__base__arrow
+          base:tooltip__base,
+          base__popup:tooltip__base__popup,
+          base__arrow:tooltip__base__arrow,
           body:tooltip__body
         "
       >