diff --git a/core/modules/widgets/fieldmangler.js b/core/modules/widgets/fieldmangler.js
index cb9dc82c8..d902e755a 100644
--- a/core/modules/widgets/fieldmangler.js
+++ b/core/modules/widgets/fieldmangler.js
@@ -74,7 +74,7 @@ FieldManglerWidget.prototype.handleAddFieldEvent = function(event) {
 	var tiddler = this.wiki.getTiddler(this.mangleTitle),
 		fieldValidatorRegEx = /^[a-z\-\._]+$/mg;
 	if(tiddler && typeof event.param === "string") {
-		var name = event.param.toLowerCase();
+		var name = event.param.toLowerCase().trim();
 		if(name !== "" && !$tw.utils.hop(tiddler.fields,name)) {
 			if(!fieldValidatorRegEx.test(name)) {
 				alert($tw.language.getString(
@@ -112,11 +112,14 @@ FieldManglerWidget.prototype.handleRemoveTagEvent = function(event) {
 
 FieldManglerWidget.prototype.handleAddTagEvent = function(event) {
 	var tiddler = this.wiki.getTiddler(this.mangleTitle);
-	if(tiddler && typeof event.param === "string" && event.param !== "") {
-		var modification = this.wiki.getModificationFields();
-		modification.tags = (tiddler.fields.tags || []).slice(0);
-		$tw.utils.pushTop(modification.tags,event.param);
-		this.wiki.addTiddler(new $tw.Tiddler(tiddler,modification));
+	if(tiddler && typeof event.param === "string") {
+		var tag = event.param.trim();
+		if(tag !== "") {
+			var modification = this.wiki.getModificationFields();
+			modification.tags = (tiddler.fields.tags || []).slice(0);
+			$tw.utils.pushTop(modification.tags,tag);
+			this.wiki.addTiddler(new $tw.Tiddler(tiddler,modification));			
+		}
 	}
 	return true;
 };