diff --git a/src/queue/index.ts b/src/queue/index.ts
index f35a382..6ea810f 100644
--- a/src/queue/index.ts
+++ b/src/queue/index.ts
@@ -3,4 +3,22 @@ import PubSub from "pubsub-js"
 
 export const KNOWLEDGE_QUEUE = Symbol("queue")
 
-PubSub.subscribe(KNOWLEDGE_QUEUE, processKnowledge)
+let isProcessing = false
+
+PubSub.subscribe(KNOWLEDGE_QUEUE, async (msg, id) => {
+  try {
+    isProcessing = true
+    await processKnowledge(msg, id)
+    isProcessing = false
+  } catch (error) {
+    console.error(error)
+    isProcessing = false
+  }
+})
+
+window.addEventListener("beforeunload", (event) => {
+  if (isProcessing) {
+    event.preventDefault()
+    event.returnValue = ""
+  }
+})