diff --git a/chrome/content/zotero/collectionTree.jsx b/chrome/content/zotero/collectionTree.jsx
index 9dc6b2c114..21de5676ad 100644
--- a/chrome/content/zotero/collectionTree.jsx
+++ b/chrome/content/zotero/collectionTree.jsx
@@ -1367,6 +1367,7 @@ var CollectionTree = class CollectionTree extends LibraryTree {
 	unregister() {
 		this._uninitialized = true;
 		Zotero.Notifier.unregisterObserver(this._unregisterID);
+		this.clearEventListeners();
 	}
 
 ////////////////////////////////////////////////////////////////////////////////
diff --git a/chrome/content/zotero/itemTree.jsx b/chrome/content/zotero/itemTree.jsx
index 192626fa43..748372ace1 100644
--- a/chrome/content/zotero/itemTree.jsx
+++ b/chrome/content/zotero/itemTree.jsx
@@ -1145,6 +1145,7 @@ var ItemTree = class ItemTree extends LibraryTree {
 		for (let id of this._prefsObserverIDs) {
 			Zotero.Prefs.unregisterObserver(id);
 		}
+		this.clearEventListeners();
 		this._writeColumnPrefsToFile(true);
 	}
 
diff --git a/chrome/content/zotero/xpcom/utilities_internal.js b/chrome/content/zotero/xpcom/utilities_internal.js
index d6fb48e231..5eda717f7f 100644
--- a/chrome/content/zotero/xpcom/utilities_internal.js
+++ b/chrome/content/zotero/xpcom/utilities_internal.js
@@ -2374,6 +2374,14 @@ Zotero.Utilities.Internal = {
 			}
 			ev.listeners.delete(listener);
 		};
+		
+		/**
+		 * Remove all listeners from all events, so that an object being torn down doesn't
+		 * keep its listeners' closures alive
+		 */
+		cls.prototype.clearEventListeners = function () {
+			this._events = null;
+		};
 
 		cls.prototype._waitForEvent = async function (event) {
 			return new Zotero.Promise((resolve) => {
diff --git a/chrome/content/zotero/zoteroPane.js b/chrome/content/zotero/zoteroPane.js
index bb47aed176..0d7ab0b0ef 100644
--- a/chrome/content/zotero/zoteroPane.js
+++ b/chrome/content/zotero/zoteroPane.js
@@ -38,6 +38,8 @@ var ZoteroPane = new function () {
 	this._listeners = {};
 	this.__defineGetter__('loaded', function () { return _loaded; });
 	var _lastSelectedItems = [];
+	// [element, listener] for the collection tree focus listener added in initCollectionsTree()
+	var _collectionsTreeFocusListener = null;
 	var lastFocusedElement = null;
 	this.lastKeyPress = null;
 	
@@ -779,6 +781,11 @@ var ZoteroPane = new function () {
 		
 		this.serializePersist();
 
+		if (_collectionsTreeFocusListener) {
+			let [elem, listener] = _collectionsTreeFocusListener;
+			elem.removeEventListener("focus", listener);
+			_collectionsTreeFocusListener = null;
+		}
 		if(this.collectionsView) this.collectionsView.unregister();
 		if(this.itemsView) this.itemsView.unregister();
 		if (_syncRemindersObserverID) {
@@ -1651,7 +1658,10 @@ var ZoteroPane = new function () {
 				dragAndDrop: true,
 				multiSelect: true
 			});
-			collectionsTree.firstChild.addEventListener("focus", ZoteroPane.collectionsView.recordCollectionTreeFocus);
+			let treeElem = collectionsTree.firstChild;
+			let focusListener = ZoteroPane.collectionsView.recordCollectionTreeFocus;
+			treeElem.addEventListener("focus", focusListener);
+			_collectionsTreeFocusListener = [treeElem, focusListener];
 		}
 		catch (e) {
 			Zotero.logError(e);