diff --git a/Customizations/SharedTagRenderings.ts b/Customizations/SharedTagRenderings.ts
index 5014ad4f7..035a61dcc 100644
--- a/Customizations/SharedTagRenderings.ts
+++ b/Customizations/SharedTagRenderings.ts
@@ -2,18 +2,20 @@ import * as questions from "../assets/tagRenderings/questions.json";
 import * as icons from "../assets/tagRenderings/icons.json";
 import {Utils} from "../Utils";
 import TagRenderingConfig from "../Models/ThemeConfig/TagRenderingConfig";
+import {TagRenderingConfigJson} from "../Models/ThemeConfig/Json/TagRenderingConfigJson";
 
 export default class SharedTagRenderings {
 
     public static SharedTagRendering: Map<string, TagRenderingConfig> = SharedTagRenderings.generatedSharedFields();
+    public static SharedTagRenderingJson: Map<string, TagRenderingConfigJson> = SharedTagRenderings.generatedSharedFieldsJsons();
     public static SharedIcons: Map<string, TagRenderingConfig> = SharedTagRenderings.generatedSharedFields(true);
 
     private static generatedSharedFields(iconsOnly = false): Map<string, TagRenderingConfig> {
-        const dict = new Map<string, TagRenderingConfig>();
-
-        function add(key, store) {
+        const configJsons = SharedTagRenderings.generatedSharedFieldsJsons(iconsOnly)
+        const d = new Map<string, TagRenderingConfig>()
+        for (const key of Array.from(configJsons.keys())) {
             try {
-                dict.set(key, new TagRenderingConfig(store[key], undefined, `SharedTagRenderings.${key}`))
+                d.set(key, new TagRenderingConfig(configJsons.get(key), undefined, `SharedTagRenderings.${key}`))
             } catch (e) {
                 if (!Utils.runningFromConsole) {
                     console.error("BUG: could not parse", key, " from questions.json or icons.json - this error happened during the build step of the SharedTagRenderings", e)
@@ -21,14 +23,19 @@ export default class SharedTagRenderings {
                 }
             }
         }
+        return d
+    }
+
+    private static generatedSharedFieldsJsons(iconsOnly = false): Map<string, TagRenderingConfigJson> {
+        const dict = new Map<string, TagRenderingConfigJson>();
 
         if (!iconsOnly) {
             for (const key in questions) {
-                add(key, questions);
+                dict.set(key, <TagRenderingConfigJson>questions[key])
             }
         }
         for (const key in icons) {
-            add(key, icons);
+            dict.set(key, <TagRenderingConfigJson>icons[key])
         }
 
         return dict;
diff --git a/Models/Constants.ts b/Models/Constants.ts
index fce9144eb..759557962 100644
--- a/Models/Constants.ts
+++ b/Models/Constants.ts
@@ -2,7 +2,7 @@ import {Utils} from "../Utils";
 
 export default class Constants {
 
-    public static vNumber = "0.9.6";
+    public static vNumber = "0.9.7";
 
     // The user journey states thresholds when a new feature gets unlocked
     public static userJourney = {
diff --git a/Models/ThemeConfig/Json/LayerConfigJson.ts b/Models/ThemeConfig/Json/LayerConfigJson.ts
index fcd11aa90..ba6371de7 100644
--- a/Models/ThemeConfig/Json/LayerConfigJson.ts
+++ b/Models/ThemeConfig/Json/LayerConfigJson.ts
@@ -256,7 +256,7 @@ export interface LayerConfigJson {
      * A special value is 'questions', which indicates the location of the questions box. If not specified, it'll be appended to the bottom of the featureInfobox.
      *
      */
-    tagRenderings?: (string | TagRenderingConfigJson) [],
+    tagRenderings?: (string | {builtin: string, override: any} | TagRenderingConfigJson) [],
 
 
     /**
diff --git a/Models/ThemeConfig/LayerConfig.ts b/Models/ThemeConfig/LayerConfig.ts
index 84ae9e472..9a5d3f322 100644
--- a/Models/ThemeConfig/LayerConfig.ts
+++ b/Models/ThemeConfig/LayerConfig.ts
@@ -214,7 +214,7 @@ export default class LayerConfig {
          * A string is interpreted as a name to call
          */
         function trs(
-            tagRenderings?: (string | TagRenderingConfigJson)[],
+            tagRenderings?: (string | { builtin: string, override: any } | TagRenderingConfigJson)[],
             readOnly = false
         ) {
             if (tagRenderings === undefined) {
@@ -224,7 +224,12 @@ export default class LayerConfig {
             return Utils.NoNull(
                 tagRenderings.map((renderingJson, i) => {
                     if (typeof renderingJson === "string") {
-                        if (renderingJson === "questions") {
+                        renderingJson = {builtin: renderingJson, override: undefined}
+                    }
+
+                    if (renderingJson["builtin"] !== undefined) {
+                        const renderingId = renderingJson["builtin"]
+                        if (renderingId === "questions") {
                             if (readOnly) {
                                 throw `A tagrendering has a question, but asking a question does not make sense here: is it a title icon or a geojson-layer? ${context}. The offending tagrendering is ${JSON.stringify(
                                     renderingJson
@@ -234,26 +239,34 @@ export default class LayerConfig {
                             return new TagRenderingConfig("questions", undefined);
                         }
 
-                        const shared =
-                            SharedTagRenderings.SharedTagRendering.get(renderingJson);
+                        if (renderingJson["override"] !== undefined) {
+                            const sharedJson = SharedTagRenderings.SharedTagRenderingJson.get(renderingId)
+                            return new TagRenderingConfig(
+                                Utils.Merge(renderingJson["override"], sharedJson),
+                                self.source.osmTags,
+                                `${context}.tagrendering[${i}]+override`
+                            );
+                        }
+
+                        const shared = SharedTagRenderings.SharedTagRendering.get(renderingId);
+
                         if (shared !== undefined) {
                             return shared;
                         }
+                        if (Utils.runningFromConsole) {
+                            return undefined;
+                        }
 
                         const keys = Array.from(
                             SharedTagRenderings.SharedTagRendering.keys()
                         );
-
-                        if (Utils.runningFromConsole) {
-                            return undefined;
-                        }
-
-                        throw `Predefined tagRendering ${renderingJson} not found in ${context}.\n    Try one of ${keys.join(
+                        throw `Predefined tagRendering ${renderingId} not found in ${context}.\n    Try one of ${keys.join(
                             ", "
                         )}\n    If you intent to output this text literally, use {\"render\": <your text>} instead"}`;
                     }
+
                     return new TagRenderingConfig(
-                        renderingJson,
+                        <TagRenderingConfigJson>renderingJson,
                         self.source.osmTags,
                         `${context}.tagrendering[${i}]`
                     );
diff --git a/Models/ThemeConfig/TagRenderingConfig.ts b/Models/ThemeConfig/TagRenderingConfig.ts
index 90c6e0a6e..1ed34a180 100644
--- a/Models/ThemeConfig/TagRenderingConfig.ts
+++ b/Models/ThemeConfig/TagRenderingConfig.ts
@@ -67,7 +67,9 @@ export default class TagRenderingConfig {
         }
         if (json.freeform) {
 
-
+            if(json.freeform.addExtraTags !== undefined && json.freeform.addExtraTags.length === undefined){
+                throw `Freeform.addExtraTags should be a list of strings - not a single string (at ${context})`
+            }
             this.freeform = {
                 key: json.freeform.key,
                 type: json.freeform.type ?? "string",