diff --git a/core/modules/utils/utils.js b/core/modules/utils/utils.js
index 234de0c75..08cb54ef9 100644
--- a/core/modules/utils/utils.js
+++ b/core/modules/utils/utils.js
@@ -699,7 +699,7 @@ exports.encodeURIComponentExtended = function(s) {
 
 // Checks whether a link target is external, i.e. not a tiddler title
 exports.isLinkExternal = function(to) {
-	var externalRegExp = /^(?:file|http|https|mailto|ftp|irc|news|obsidian|data|skype):[^\s<>{}\[\]`|"\\^]+(?:\/|\b)/i;
+	var externalRegExp = /^(?:file|http|https|mailto|ftp|irc|news|obsidian|data|skype|zotero):[^\s<>{}\[\]`|"\\^]+(?:\/|\b)/i;
 	return externalRegExp.test(to);
 };
 
diff --git a/plugins/tiddlywiki/tw2parser/wikitextrules.js b/plugins/tiddlywiki/tw2parser/wikitextrules.js
index 068bb9757..a627ad0d4 100755
--- a/plugins/tiddlywiki/tw2parser/wikitextrules.js
+++ b/plugins/tiddlywiki/tw2parser/wikitextrules.js
@@ -127,7 +127,7 @@ var insertMacroCall = function(w,output,macroName,paramString) {
 
 
 var isLinkExternal = function(to) {
-	var externalRegExp = /(?:file|http|https|mailto|ftp|irc|news|obsidian|data|skype):[^\s'"]+(?:\/|\b)/i;
+	var externalRegExp = /(?:file|http|https|mailto|ftp|irc|news|obsidian|data|skype|zotero):[^\s'"]+(?:\/|\b)/i;
 	return externalRegExp.test(to);
 };
 var rules = [