diff --git a/devtools/client/responsive.html/browser/web-navigation.js b/devtools/client/responsive.html/browser/web-navigation.js
index da96eb43151b..de535540e3e8 100644
--- a/devtools/client/responsive.html/browser/web-navigation.js
+++ b/devtools/client/responsive.html/browser/web-navigation.js
@@ -79,9 +79,9 @@ BrowserElementWebNavigation.prototype = {
       postData: postData ? readInputStreamToString(postData) : null,
       headers: headers ? readInputStreamToString(headers) : null,
       baseURI: baseURI ? baseURI.spec : null,
-      triggeringPrincipal: triggeringPrincipal
-                           ? Utils.serializePrincipal(triggeringPrincipal)
-                           : Services.scriptSecurityManager.createNullPrincipal({}),
+      triggeringPrincipal: Utils.serializePrincipal(
+                           triggeringPrincipal ||
+                           Services.scriptSecurityManager.createNullPrincipal({})),
       requestTime: telemetry.msSystemNow(),
     });
   },
diff --git a/toolkit/actors/WebNavigationChild.jsm b/toolkit/actors/WebNavigationChild.jsm
index d53d4163f146..2b1a54a2bdd3 100644
--- a/toolkit/actors/WebNavigationChild.jsm
+++ b/toolkit/actors/WebNavigationChild.jsm
@@ -108,7 +108,9 @@ class WebNavigationChild extends ActorChild {
     if (triggeringPrincipal)
       triggeringPrincipal = Utils.deserializePrincipal(triggeringPrincipal);
     if (!triggeringPrincipal) {
-      triggeringPrincipal = Services.scriptSecurityManager.getSystemPrincipal({});
+      // If we don't have a triggering principal we won't be able to continue the load.
+      let debug = Cc["@mozilla.org/xpcom/debug;1"].getService(Ci.nsIDebug2);
+      debug.abort("WebNavigationChild.js", 112);
     }
     let loadURIOptions = {
       triggeringPrincipal,
diff --git a/toolkit/components/remotebrowserutils/RemoteWebNavigation.js b/toolkit/components/remotebrowserutils/RemoteWebNavigation.js
index a7b841e02ac0..9932968d69a4 100644
--- a/toolkit/components/remotebrowserutils/RemoteWebNavigation.js
+++ b/toolkit/components/remotebrowserutils/RemoteWebNavigation.js
@@ -100,7 +100,7 @@ RemoteWebNavigation.prototype = {
       headers: aLoadURIOptions.headers ? Utils.serializeInputStream(aLoadURIOptions.headers) : null,
       baseURI: aLoadURIOptions.baseURI ? aLoadURIOptions.baseURI.spec : null,
       triggeringPrincipal: Utils.serializePrincipal(
-          aLoadURIOptions.triggeringPrincipal || Services.scriptSecurityManager.createNullPrincipal({})),
+                           aLoadURIOptions.triggeringPrincipal || Services.scriptSecurityManager.createNullPrincipal({})),
       requestTime: Services.telemetry.msSystemNow(),
     });
   },
diff --git a/toolkit/modules/E10SUtils.jsm b/toolkit/modules/E10SUtils.jsm
index 8f95f84051ad..ff7045c75345 100644
--- a/toolkit/modules/E10SUtils.jsm
+++ b/toolkit/modules/E10SUtils.jsm
@@ -332,9 +332,7 @@ var E10SUtils = {
         uri: aURI.spec,
         flags: aFlags || Ci.nsIWebNavigation.LOAD_FLAGS_NONE,
         referrer: aReferrer ? aReferrer.spec : null,
-        triggeringPrincipal: aTriggeringPrincipal
-                             ? Utils.serializePrincipal(aTriggeringPrincipal)
-                             : null,
+        triggeringPrincipal: Utils.serializePrincipal(aTriggeringPrincipal || Services.scriptSecurityManager.createNullPrincipal({})),
         reloadInFreshProcess: !!aFreshProcess,
       },
       historyIndex: sessionHistory.legacySHistory.requestedIndex,