And another one

lib/activitypub/middleware/http-signature.ts

@@ -25,6 +25,9 @@ export = async (req: Request, res: Response, next: NextFunction) => {
 				console.log(`Could not retrieve actor ${req.body.actor} to validate HTTP signature for`, req.body);
 				res.status(401).end("Could not retrieve actor to validate HTTP signature");
 			}
+		} else if (!actor.publicKey) {
+			console.log(`Could not validate HTTP signature, actor missing public key: ${actor}`);
+			res.status(401).end("Actor missing public key.")
 		} else if (!validate(req, actor.publicKey.publicKeyPem)) {
 			console.log(`Could not validate HTTP signature for ${req.body.actor}`);
 			res.status(401).end("Could not validate HTTP signature");