diff --git a/packages/eslint-plugin/src/util/explicitReturnTypeUtils.ts b/packages/eslint-plugin/src/util/explicitReturnTypeUtils.ts
index 1cfc834c1c1b..2604e6185cc0 100644
--- a/packages/eslint-plugin/src/util/explicitReturnTypeUtils.ts
+++ b/packages/eslint-plugin/src/util/explicitReturnTypeUtils.ts
@@ -337,15 +337,12 @@ function ancestorHasReturnType(node: FunctionNode): boolean {
       // const x: Foo = () => {};
       // Assume that a typed variable types the function expression
       case AST_NODE_TYPES.VariableDeclarator:
-        if (ancestor.id.typeAnnotation) {
-          return true;
-        }
-        break;
+        return !!ancestor.id.typeAnnotation;
+
       case AST_NODE_TYPES.PropertyDefinition:
-        if (ancestor.typeAnnotation) {
-          return true;
-        }
-        break;
+        return !!ancestor.typeAnnotation;
+      case AST_NODE_TYPES.ExpressionStatement:
+        return false;
     }
 
     ancestor = ancestor.parent;
diff --git a/packages/eslint-plugin/tests/rules/explicit-function-return-type.test.ts b/packages/eslint-plugin/tests/rules/explicit-function-return-type.test.ts
index 2036927e0ca9..7556cee3ce77 100644
--- a/packages/eslint-plugin/tests/rules/explicit-function-return-type.test.ts
+++ b/packages/eslint-plugin/tests/rules/explicit-function-return-type.test.ts
@@ -1016,6 +1016,74 @@ class Foo {
     },
     {
       code: `
+function foo(): any {
+  const bar = () => () => console.log('aa');
+}
+      `,
+      options: [
+        {
+          allowTypedFunctionExpressions: true,
+        },
+      ],
+      errors: [
+        {
+          messageId: 'missingReturnType',
+          line: 3,
+          endLine: 3,
+          column: 24,
+          endColumn: 26,
+        },
+      ],
+    },
+    {
+      code: `
+let anyValue: any;
+function foo(): any {
+  anyValue = () => () => console.log('aa');
+}
+      `,
+      options: [
+        {
+          allowTypedFunctionExpressions: true,
+        },
+      ],
+      errors: [
+        {
+          messageId: 'missingReturnType',
+          line: 4,
+          endLine: 4,
+          column: 23,
+          endColumn: 25,
+        },
+      ],
+    },
+    {
+      code: `
+class Foo {
+  foo(): any {
+    const bar = () => () => {
+      return console.log('foo');
+    };
+  }
+}
+      `,
+      options: [
+        {
+          allowTypedFunctionExpressions: true,
+        },
+      ],
+      errors: [
+        {
+          messageId: 'missingReturnType',
+          line: 4,
+          endLine: 4,
+          column: 26,
+          endColumn: 28,
+        },
+      ],
+    },
+    {
+      code: `
 var funcExpr = function () {
   return 'test';
 };
@@ -1171,6 +1239,31 @@ const x: Foo = {
         },
       ],
     },
+    {
+      code: `
+function foo(): any {
+  class Foo {
+    foo = () => () => {
+      return console.log('foo');
+    };
+  }
+}
+      `,
+      options: [
+        {
+          allowTypedFunctionExpressions: true,
+        },
+      ],
+      errors: [
+        {
+          messageId: 'missingReturnType',
+          line: 4,
+          endLine: 4,
+          column: 20,
+          endColumn: 22,
+        },
+      ],
+    },
     {
       code: '() => () => {};',
       options: [{ allowHigherOrderFunctions: true }],
diff --git a/packages/website/src/components/editor/LoadedEditor.tsx b/packages/website/src/components/editor/LoadedEditor.tsx
index 01434408db7d..6dab67a39278 100644
--- a/packages/website/src/components/editor/LoadedEditor.tsx
+++ b/packages/website/src/components/editor/LoadedEditor.tsx
@@ -135,14 +135,14 @@ export const LoadedEditor: React.FC<LoadedEditorProps> = ({
       monaco.editor.setModelMarkers(model, 'eslint', diagnostics);
       updateMarkers();
     });
-    return () => disposable();
+    return (): void => disposable();
   }, [webLinter, monaco, codeActions, updateMarkers]);
 
   useEffect(() => {
     const disposable = webLinter.onParse((uri, model) => {
       onASTChange(model);
     });
-    return () => disposable();
+    return (): void => disposable();
   }, [webLinter, onASTChange]);
 
   useEffect(() => {
@@ -178,7 +178,7 @@ export const LoadedEditor: React.FC<LoadedEditorProps> = ({
       'typescript',
       createProvideCodeActions(codeActions),
     );
-    return () => disposable.dispose();
+    return (): void => disposable.dispose();
   }, [codeActions, monaco]);
 
   useEffect(() => {
@@ -191,7 +191,9 @@ export const LoadedEditor: React.FC<LoadedEditorProps> = ({
         }
       }
     });
-    return () => disposable.dispose();
+    return (): void => {
+      disposable.dispose();
+    };
   }, [editor, tabs.eslintrc]);
 
   useEffect(() => {
@@ -204,7 +206,7 @@ export const LoadedEditor: React.FC<LoadedEditorProps> = ({
         }
       }, 150),
     );
-    return () => disposable.dispose();
+    return (): void => disposable.dispose();
   }, [onSelect, editor, tabs.code]);
 
   useEffect(() => {
@@ -227,7 +229,7 @@ export const LoadedEditor: React.FC<LoadedEditorProps> = ({
         }
       },
     });
-    return () => disposable.dispose();
+    return (): void => disposable.dispose();
   }, [editor, monaco, webLinter]);
 
   useEffect(() => {
@@ -243,7 +245,7 @@ export const LoadedEditor: React.FC<LoadedEditorProps> = ({
       }),
     ];
 
-    return () => {
+    return (): void => {
       closable.forEach(c => c.close());
     };
   }, [system, onChange]);
@@ -255,14 +257,14 @@ export const LoadedEditor: React.FC<LoadedEditorProps> = ({
         system.writeFile(model.uri.path, model.getValue());
       }
     });
-    return () => disposable.dispose();
+    return (): void => disposable.dispose();
   }, [editor, system]);
 
   useEffect(() => {
     const disposable = monaco.editor.onDidChangeMarkers(() => {
       updateMarkers();
     });
-    return () => disposable.dispose();
+    return (): void => disposable.dispose();
   }, [monaco.editor, updateMarkers]);
 
   const resize = useMemo(() => {
diff --git a/packages/website/src/hooks/useMediaQuery.ts b/packages/website/src/hooks/useMediaQuery.ts
index a092478ac882..422570aee8ef 100644
--- a/packages/website/src/hooks/useMediaQuery.ts
+++ b/packages/website/src/hooks/useMediaQuery.ts
@@ -29,7 +29,7 @@ const useMediaQuery = (mediaQuery: string): boolean => {
     }
 
     documentChangeHandler();
-    return () => {
+    return (): void => {
       try {
         mediaQueryList.removeEventListener('change', documentChangeHandler);
       } catch {