chore: handle function not set (preserve non-breaking)

platform/viewer/src/connectedComponents/ToolbarRow.js

@@ -74,7 +74,9 @@ class ToolbarRow extends Component {
 
         // It's a bit beefy to pass studies; probably only need to be reactive on `studyInstanceUIDs` and activeViewport?
         // Note: This does not cleanly handle `studies` prop updating with panel open
-        const isDisabled = menuOption.isDisabled(this.props.studies);
+        const isDisabled =
+          typeof menuOption.isDisabled === 'function' &&
+          menuOption.isDisabled(this.props.studies);
 
         if (hasActiveContext && !isDisabled) {
           const menuOptionEntry = {