diff --git a/extension/_locales/en/messages.json b/extension/_locales/en/messages.json
index 18246bba..f832d022 100644
--- a/extension/_locales/en/messages.json
+++ b/extension/_locales/en/messages.json
@@ -1,23 +1,23 @@
 {
-  "advanced": {
+  "WEBCAT_advanced": {
     "message": "Advanced"
   },
-  "hideAdvanced": {
+  "WEBCAT_hideAdvanced": {
     "message": "Hide advanced"
   },
-  "thisSite": {
+  "WEBCAT_thisSite": {
     "message": "this site"
   },
-  "webcatVerificationSuccessful": {
+  "WEBCAT_webcatVerificationSuccessful": {
     "message": "WEBCAT verification successful"
   },
-  "webcatVerificationFailed": {
+  "WEBCAT_webcatVerificationFailed": {
     "message": "WEBCAT verification failed"
   },
-  "webcatIsRunning": {
+  "WEBCAT_webcatIsRunning": {
     "message": "WEBCAT is running"
   },
-  "webcatIsUnavailable": {
+  "WEBCAT_webcatIsUnavailable": {
     "message": "WEBCAT unavailable on this site."
   }
 }
diff --git a/extension/_locales/fi/messages.json b/extension/_locales/fi/messages.json
index bdc38c0b..3608e4ed 100644
--- a/extension/_locales/fi/messages.json
+++ b/extension/_locales/fi/messages.json
@@ -1,47 +1,47 @@
 {
-  "warningSecurityRisk": {
+  "WEBCAT_warningSecurityRisk": {
     "message": "Varoitus: Tietoturvariski"
   },
-  "didNotVerify": {
+  "WEBCAT_didNotVerify": {
     "message": "Ei varmennettu"
   },
-  "errorShortDesc": {
+  "WEBCAT_errorShortDesc": {
     "message": "WEBCAT ei voinut varmentaa, että koodi, jonka $1 tarjoili, vastaa allekirjoitettua manifestia, joten sivu estettiin."
   },
-  "thisSite": {
+  "WEBCAT_thisSite": {
     "message": "tämä sivusto"
   },
-  "advanced": {
+  "WEBCAT_advanced": {
     "message": "Lisätietoja"
   },
-  "hideAdvanced": {
+  "WEBCAT_hideAdvanced": {
     "message": "Piilota lisätiedot"
   },
-  "goBack": {
+  "WEBCAT_goBack": {
     "message": "Palaa takaisin"
   },
-  "whatYouCanDo": {
+  "WEBCAT_whatYouCanDo": {
     "message": "Ongelma johtuu sivustosta, ei verkkoyhteydestäsi. Koodi tai ympäristö, jonka sivusto tarjoili, ei vastaa sen kehittäjien kryptografista allekirjoitusta, joten WEBCAT esti sivun pitääkseen sinut turvassa. Voit ilmoittaa ongelmasta sivuston omistajalle, tai jos luulet tämän olevan bugi, raportoida sen $1."
   },
-  "webcatRepository": {
+  "WEBCAT_webcatRepository": {
     "message": "WEBCATin tietovarastoon"
   },
-  "file": {
+  "WEBCAT_file": {
     "message": "Tiedosto: $1"
   },
-  "errorCode": {
+  "WEBCAT_errorCode": {
     "message": "Virhekoodi: $1"
   },
-  "webcatVerificationSuccessful": {
+  "WEBCAT_webcatVerificationSuccessful": {
     "message": "WEBCAT-varmennus onnistui"
   },
-  "webcatVerificationFailed": {
+  "WEBCAT_webcatVerificationFailed": {
     "message": "WEBCAT-varmennus epäonnistui"
   },
-  "webcatIsRunning": {
+  "WEBCAT_webcatIsRunning": {
     "message": "WEBCAT on käynnissä"
   },
-  "webcatIsUnavailable": {
+  "WEBCAT_webcatIsUnavailable": {
     "message": "WEBCAT ei käytettävissä tällä sivustolla."
   }
 }
diff --git a/extension/manifest.json b/extension/manifest.json
index 0ee41428..ae716790 100644
--- a/extension/manifest.json
+++ b/extension/manifest.json
@@ -47,7 +47,7 @@
       "48": "icons/light/webcat.SVG",
       "128": "icons/light/webcat.SVG"
     },
-    "default_title": "__MSG_webcatIsUnavailable__"
+    "default_title": "__MSG_WEBCAT_webcatIsUnavailable__"
   },
   "default_locale": "en"
 }
diff --git a/extension/pages/error.js b/extension/pages/error.js
index 0d0e5521..ec819640 100644
--- a/extension/pages/error.js
+++ b/extension/pages/error.js
@@ -5,7 +5,7 @@ document.addEventListener("DOMContentLoaded", () => {
         (child) => child.outerHTML,
       );
       const msg = browser.i18n.getMessage(
-        el.getAttribute("data-i18n"),
+        "WEBCAT_" + el.getAttribute("data-i18n"),
         substitutions,
       );
       if (msg === "") {
@@ -22,7 +22,7 @@ document.addEventListener("DOMContentLoaded", () => {
   const host = params.get("host") || "";
   const file = params.get("file") || "";
 
-  setText("error-host", host || browser.i18n.getMessage("thisSite"));
+  setText("error-host", host || browser.i18n.getMessage("WEBCAT_thisSite"));
   setText("debug-code", code);
 
   if (file) {
@@ -36,8 +36,8 @@ document.addEventListener("DOMContentLoaded", () => {
     advancedPanel.hidden = !advancedPanel.hidden;
     advancedButton.setAttribute("aria-expanded", String(!advancedPanel.hidden));
     advancedButton.textContent = advancedPanel.hidden
-      ? browser.i18n.getMessage("advanced")
-      : browser.i18n.getMessage("hideAdvanced");
+      ? browser.i18n.getMessage("WEBCAT_advanced")
+      : browser.i18n.getMessage("WEBCAT_hideAdvanced");
   });
 
   // The error page took a history slot