diff --git a/src/components/Editor.vue b/src/components/Editor.vue
index 9d256b9b194..18c3fc3192b 100644
--- a/src/components/Editor.vue
+++ b/src/components/Editor.vue
@@ -703,7 +703,9 @@ export default {
 
 		async close() {
 			await this.$syncService.sendRemainingSteps()
+				.catch(err => logger.warn('Failed to send remaining steps', { err }))
 			await this.disconnect()
+				.catch(err => logger.warn('Failed to disconnect', { err }))
 			if (this.$editor) {
 				try {
 					this.unlistenEditorEvents()
diff --git a/src/services/Outbox.ts b/src/services/Outbox.ts
index 6c27a04872f..2ca82416b8d 100644
--- a/src/services/Outbox.ts
+++ b/src/services/Outbox.ts
@@ -17,7 +17,7 @@ export default class Outbox {
 
 	storeStep(step: Uint8Array) {
 		const encoded = encodeArrayBuffer(step)
-		if (encoded < 'AAA') {
+		if (encoded < 'AAA' || encoded > 'Ag') {
 			logger.warn('Unexpected step type:', { step, encoded })
 			return
 		}
@@ -29,11 +29,7 @@ export default class Outbox {
 			this.#syncUpdate = encoded
 			return
 		}
-		if (encoded < 'Ag') {
-			this.#awarenessUpdate = encoded
-			return
-		}
-		logger.warn('Unexpected step type:', { step, encoded })
+		this.#awarenessUpdate = encoded
 	}
 
 	getDataToSend(): Sendable {
@@ -48,7 +44,7 @@ export default class Outbox {
 	}
 
 	/*
-	 * Clear data that has just been
+	 * Clear data that has just been sent.
 	 *
 	 * Only clear data that has not changed in the meantime.
 	 * @param {Sendable} - data that was to the server
diff --git a/src/services/SyncService.js b/src/services/SyncService.js
index 669731503d7..fc2f035a5b1 100644
--- a/src/services/SyncService.js
+++ b/src/services/SyncService.js
@@ -307,8 +307,8 @@ class SyncService {
 	}
 
 	sendRemainingSteps() {
-		if (!this.outbox.hasUpdate()) {
-			return
+		if (!this.#outbox.hasUpdate) {
+			return Promise.resolve()
 		}
 		logger.debug('sending final steps')
 		return this.sendStepsNow().catch(err => logger.error(err))