diff --git a/chrome/content/zotero/xpcom/data/item.js b/chrome/content/zotero/xpcom/data/item.js
index 5b10603d8..895741fde 100644
--- a/chrome/content/zotero/xpcom/data/item.js
+++ b/chrome/content/zotero/xpcom/data/item.js
@@ -4100,7 +4100,7 @@ Zotero.Item.prototype.toJSON = Zotero.Promise.coroutine(function* (options, patc
 	yield this.loadCollections();
 	obj.collections = this.getCollections().map(function (id) {
 		return this.ContainerObjectsClass.getLibraryAndKeyFromID(id)[1];
-	});
+	}.bind(this));
 	
 	// Relations
 	yield this.loadRelations();
diff --git a/components/zotero-protocol-handler.js b/components/zotero-protocol-handler.js
index c3f5630af..1b1c1203c 100644
--- a/components/zotero-protocol-handler.js
+++ b/components/zotero-protocol-handler.js
@@ -1186,8 +1186,6 @@ AsyncChannel.prototype = {
 		Zotero.debug("AsyncChannel's asyncOpen called");
 		var t = new Date;
 		
-		let channel = this;
-		
 		// Proxy requests to other zotero:// URIs
 		let uri2 = this.URI.clone();
 		if (uri2.path.startsWith('/proxy/')) {