diff --git a/Models/ThemeConfig/TagRenderingConfig.ts b/Models/ThemeConfig/TagRenderingConfig.ts
index e680143578..c790be1808 100644
--- a/Models/ThemeConfig/TagRenderingConfig.ts
+++ b/Models/ThemeConfig/TagRenderingConfig.ts
@@ -109,7 +109,11 @@ export default class TagRenderingConfig {
             if (json.freeform.addExtraTags !== undefined && json.freeform.addExtraTags.map === undefined) {
                 throw `Freeform.addExtraTags should be a list of strings - not a single string (at ${context})`
             }
-           const type = json.freeform.type ?? "string"
+            const type = json.freeform.type ?? "string"
+            
+            if(ValidatedTextField.AvailableTypes().indexOf(type ) < 0){
+                throw "At "+context+".freeform.type is an unknown type: "+type+"; try one of "+ValidatedTextField.AvailableTypes().join(", ")
+            }
 
             let placeholder: Translation = Translations.T(json.freeform.placeholder)
             if (placeholder === undefined) {
diff --git a/UI/Input/ValidatedTextField.ts b/UI/Input/ValidatedTextField.ts
index 9976ca3887..1acad39716 100644
--- a/UI/Input/ValidatedTextField.ts
+++ b/UI/Input/ValidatedTextField.ts
@@ -546,7 +546,7 @@ class LengthTextField extends TextFieldDef {
 
     constructor() {
         super(
-            "decimal", "A geographical length in meters (rounded at two points). Will give an extra minimap with a measurement tool. Arguments: [ zoomlevel, preferredBackgroundMapType (comma separated) ], e.g. `[\"21\", \"map,photo\"]"
+            "length", "A geographical length in meters (rounded at two points). Will give an extra minimap with a measurement tool. Arguments: [ zoomlevel, preferredBackgroundMapType (comma separated) ], e.g. `[\"21\", \"map,photo\"]"
         )
     }