diff --git a/chrome/content/zotero/xpcom/integration.js b/chrome/content/zotero/xpcom/integration.js
index 772fee8d8..9ab5a1e21 100644
--- a/chrome/content/zotero/xpcom/integration.js
+++ b/chrome/content/zotero/xpcom/integration.js
@@ -1130,7 +1130,7 @@ Zotero.Integration.Fields.prototype.addEditCitation = Zotero.Promise.coroutine(f
 			if (fields[i].equals(field._field)) {
 				// This is needed, because LibreOffice integration plugin caches the field code instead of asking
 				// the document every time when calling #getCode().
-				field._field = fields[i];
+				field = new Zotero.Integration.CitationField(fields[i]);
 				return i;
 			}
 		}
@@ -1967,10 +1967,9 @@ Zotero.Integration.Field = class {
 		if (field instanceof Zotero.Integration.Field) {
 			throw new Error("Trying to instantiate Integration.Field with Integration.Field, not doc field");
 		}
-		// This is not the best solution in terms of performance
-		for (let prop in field) {
-			if (prop[0] != '_' && !(prop in this)) {
-				this[prop] = field[prop].bind ? field[prop].bind(field) : field[prop];
+		for (let func of Zotero.Integration.Field.INTERFACE) {
+			if (!(func in this)) {
+				this[func] = field[func].bind(field);
 			}
 		}
 		this._field = field;
@@ -2018,6 +2017,8 @@ Zotero.Integration.Field = class {
 		return isRich;
 	}
 };
+Zotero.Integration.Field.INTERFACE = ['delete', 'removeCode', 'select', 'setText',
+	'getText', 'setCode', 'getCode', 'equals', 'getNoteIndex'];
 
 /**
  * Load existing field in document and return correct instance of field type