Use semantic list elements for menu lists and tab lists

res/css/views/context_menus/_IconizedContextMenu.pcss

@@ -18,6 +18,9 @@ limitations under the License.
 .mx_IconizedContextMenu {
     min-width: 146px;
     width: max-content;
+    // override default ul styles
+    margin: 0;
+    padding: 0;
 
     .mx_IconizedContextMenu_optionList {
         & > * {

src/components/structures/TabbedView.tsx

@@ -121,6 +121,7 @@ export default class TabbedView<T extends string> extends React.Component<IProps
                 role="tab"
                 aria-selected={isActive}
                 aria-controls={id}
+                element="li"
             >
                 {tabIcon}
                 <span className="mx_TabbedView_tabLabel_text" id={`${id}_label`}>
@@ -166,14 +167,14 @@ export default class TabbedView<T extends string> extends React.Component<IProps
                     handleUpDown={this.props.tabLocation == TabLocation.LEFT}
                 >
                     {({ onKeyDownHandler }) => (
-                        <div
+                        <ul
                             className="mx_TabbedView_tabLabels"
                             role="tablist"
                             aria-orientation={this.props.tabLocation == TabLocation.LEFT ? "vertical" : "horizontal"}
                             onKeyDown={onKeyDownHandler}
                         >
                             {labels}
-                        </div>
+                        </ul>
                     )}
                 </RovingTabIndexProvider>
                 {panel}

src/components/views/context_menus/IconizedContextMenu.tsx

@@ -132,6 +132,7 @@ export const IconizedContextMenuOption: React.FC<IOptionProps> = ({
                 mx_IconizedContextMenu_itemDestructive: isDestructive,
             })}
             label={label}
+            element="li"
         >
             {iconClassName && <span className={classNames("mx_IconizedContextMenu_icon", iconClassName)} />}
             <span className="mx_IconizedContextMenu_label">{label}</span>
@@ -171,7 +172,9 @@ const IconizedContextMenu: React.FC<React.PropsWithChildren<IProps>> = ({ classN
 
     return (
         <ContextMenu chevronFace={ChevronFace.None} {...props}>
-            <div className={classes}>{children}</div>
+            <ul role="none" className={classes}>
+                {children}
+            </ul>
         </ContextMenu>
     );
 };