diff --git a/includes/TemplateDataBlob.php b/includes/TemplateDataBlob.php
index 108b6a9f..8546b613 100644
--- a/includes/TemplateDataBlob.php
+++ b/includes/TemplateDataBlob.php
@@ -312,10 +312,12 @@ class TemplateDataBlob {
 					return Status::newFatal( 'templatedata-invalid-type',
 						"params.{$paramName}.aliases", 'array' );
 				}
-				foreach ( $paramObj->aliases as $i => $alias ) {
-					if ( !is_string( $alias ) ) {
+				foreach ( $paramObj->aliases as $i => &$alias ) {
+					if ( is_int( $alias ) ) {
+						$alias = (string)$alias;
+					} elseif ( !is_string( $alias ) ) {
 						return Status::newFatal( 'templatedata-invalid-type',
-							"params.{$paramName}.aliases[$i]", 'string' );
+							"params.{$paramName}.aliases[$i]", 'int|string' );
 					}
 				}
 			} else {
diff --git a/modules/ext.templateDataGenerator.editTemplatePage/Dialog.js b/modules/ext.templateDataGenerator.editTemplatePage/Dialog.js
index 7fb59a6b..5cd00298 100644
--- a/modules/ext.templateDataGenerator.editTemplatePage/Dialog.js
+++ b/modules/ext.templateDataGenerator.editTemplatePage/Dialog.js
@@ -1103,6 +1103,11 @@ Dialog.prototype.changeParamPropertyInput = function ( paramKey, propName, value
 			propInput.selectItem( propInput.findItemFromData( value ) );
 		} else if ( prop.type === 'boolean' ) {
 			propInput.setSelected( !!value );
+		} else if ( prop.type === 'array' ) {
+			propInput.setValue( value.map( function ( v ) {
+				// TagMultiselectWidget accepts nothing but strings or objects with a .data property
+				return v && v.data ? v : String( v );
+			} ) );
 		} else {
 			if ( languageProps.indexOf( propName ) !== -1 ) {
 				propInput.setValue( value[ lang ] );
diff --git a/tests/phpunit/TemplateDataBlobTest.php b/tests/phpunit/TemplateDataBlobTest.php
index a2678d6d..98ee5b68 100644
--- a/tests/phpunit/TemplateDataBlobTest.php
+++ b/tests/phpunit/TemplateDataBlobTest.php
@@ -114,6 +114,10 @@ class TemplateDataBlobTest extends MediaWikiIntegrationTestCase {
 				'input' => '{ "params": { "a": { "aliases": "" } } }',
 				'status' => '(templatedata-invalid-type: params.a.aliases, array)',
 			],
+			[
+				'input' => '{ "params": { "a": { "aliases": [ "1", 2, {} ] } } }',
+				'status' => '(templatedata-invalid-type: params.a.aliases[2], int|string)',
+			],
 			[
 				'input' => '{ "params": { "a": { "autovalue": [] } } }',
 				'status' => '(templatedata-invalid-type: params.a.autovalue, string)',
@@ -134,6 +138,10 @@ class TemplateDataBlobTest extends MediaWikiIntegrationTestCase {
 				'input' => '{ "params": { "a": { "suggestedvalues": "" } } }',
 				'status' => '(templatedata-invalid-type: params.a.suggestedvalues, array)',
 			],
+			[
+				'input' => '{ "params": { "a": { "suggestedvalues": [ {} ] } } }',
+				'status' => '(templatedata-invalid-type: params.a.suggestedvalues[0], string)',
+			],
 			[
 				'input' => '{
 					"params": {
@@ -209,9 +217,7 @@ class TemplateDataBlobTest extends MediaWikiIntegrationTestCase {
 							"example": null,
 							"required": false,
 							"suggested": true,
-							"aliases": [
-								"1"
-							]
+							"aliases": [ 1 ]
 						}
 					}
 				}