Make entire thread panel tile clickable (matrix-org#7371)

Author: Germain

res/css/views/rooms/_EventTile.scss

@@ -776,6 +776,17 @@ $left-gutter: 64px;
         background-color: $quinary-content;
     }
 
+    &::before {
+        content: "";
+        position: absolute;
+        top: 0;
+        bottom: 0;
+        left: 0;
+        right: 0;
+        /* enough to cover all sibling elements */
+        z-index: 10;
+    }
+
     &:last-child {
         &::after {
             content: unset;

src/components/views/rooms/EventTile.tsx

@@ -1411,13 +1411,12 @@ export default class EventTile extends React.Component<IProps, IState> {
                         "data-notification": this.state.threadNotification,
                         "onMouseEnter": () => this.setState({ hover: true }),
                         "onMouseLeave": () => this.setState({ hover: false }),
-
+                        "onClick": () => dispatchShowThreadEvent(this.props.mxEvent),
                     }, <>
                         { sender }
                         { avatar }
                         <div
                             className={lineClasses}
-                            onClick={() => dispatchShowThreadEvent(this.props.mxEvent)}
                             key="mx_EventTile_line"
                         >
                             { linkedTimestamp }