diff --git a/src/org/thoughtcrime/securesms/WebxdcActivity.java b/src/org/thoughtcrime/securesms/WebxdcActivity.java
index 6edeac9be..159a38f8c 100644
--- a/src/org/thoughtcrime/securesms/WebxdcActivity.java
+++ b/src/org/thoughtcrime/securesms/WebxdcActivity.java
@@ -33,8 +33,6 @@ import java.io.InputStream;
 
 public class WebxdcActivity extends WebViewActivity implements DcEventCenter.DcEventDelegate  {
   private static final String TAG = WebxdcActivity.class.getSimpleName();
-  private static final String INTERNAL_SCHEMA = "webxdc";
-  private static final String INTERNAL_DOMAIN = "local.app";
   private DcContext dcContext;
   private DcMsg dcAppMsg;
 
@@ -74,7 +72,11 @@ public class WebxdcActivity extends WebViewActivity implements DcEventCenter.DcE
     webSettings.setAllowUniversalAccessFromFileURLs(false);
     webView.addJavascriptInterface(new InternalJSApi(), "InternalJSApi");
 
-    webView.loadUrl(INTERNAL_SCHEMA + "://" + INTERNAL_DOMAIN + "/index.html");
+    // `msg_id` in the subdomain makes sure, different apps using same files do not share the same cache entry
+    // (WebView may use a global cache shared across objects).
+    // (a random-id would also work, but would need maintenance and does not add benefits as we regard the file-part interceptRequest() only,
+    // also a random-id is not that useful for debugging)
+    webView.loadUrl("webxdc://msg" + appMessageId + ".localhost/index.html");
 
     Util.runOnAnyBackgroundThread(() -> {
       JSONObject info = this.dcAppMsg.getWebxdcInfo();