fedimbed: errors dump stack now

src/modules/fedimbed.js

@@ -712,7 +712,10 @@ events.add("messageCreate", "fedimbed", async function (msg) {
             `Hit "${service}" for "${url}", processing now.`
           );
           await processUrl(msg, url, hasSpoiler).catch((err) => {
-            logger.error("fedimbed", `Error processing "${url}": ${err}`);
+            logger.error(
+              "fedimbed",
+              `Error processing "${url}":\n` + err.stack
+            );
           });
           break;
         }