ignore message errors

lib/frame-tree/content/frame-tree.js

@@ -109,9 +109,7 @@ this.FrameTree = this.FrameTree || (() => {
 				}
 				if (!pendingCount || pendingCount == 1) {
 					browser.runtime.sendMessage({ method: "FrameTree.initResponse" })
-						.catch(error => {
-							//ignored
-						});
+						.catch(() => { /* ignored */ });
 				}
 			}
 		} else {