Merge pull request #16659 from agentbellnorm/techdocs/remove-warnings

[TechDocs] remove warnings

plugins/techdocs-react/package.json

@@ -39,7 +39,7 @@
     "@backstage/core-plugin-api": "workspace:^",
     "@backstage/version-bridge": "workspace:^",
     "@material-ui/core": "^4.12.2",
-    "@material-ui/lab": "4.0.0-alpha.57",
+    "@material-ui/lab": "4.0.0-alpha.61",
     "@material-ui/styles": "^4.11.0",
     "jss": "~10.10.0",
     "lodash": "^4.17.21",

plugins/techdocs-react/src/hooks.ts

@@ -84,11 +84,13 @@ export const useShadowRootSelection = (waitMillis: number = 0) => {
 
   useEffect(() => {
     window.document.addEventListener('selectionchange', handleSelectionChange);
-    return () =>
+    return () => {
+      handleSelectionChange.cancel();
       window.document.removeEventListener(
         'selectionchange',
         handleSelectionChange,
       );
+    };
   }, [handleSelectionChange]);
 
   return selection;