diff --git a/platform/firefox/vapi-common.js b/platform/firefox/vapi-common.js
index 9cd21bb82..a2e513797 100644
--- a/platform/firefox/vapi-common.js
+++ b/platform/firefox/vapi-common.js
@@ -74,6 +74,9 @@ vAPI.insertHTML = (function() {
     const parser = Components.classes['@mozilla.org/parserutils;1']
         .getService(Components.interfaces.nsIParserUtils);
 
+    // https://github.com/gorhill/uBlock/issues/845
+    // Apparently dashboard pages execute with `about:blank` principal.
+
     return function(node, html) {
         while ( node.firstChild ) {
             node.removeChild(node.firstChild);
@@ -83,7 +86,7 @@ vAPI.insertHTML = (function() {
             html,
             parser.SanitizerAllowStyle,
             false,
-            Services.io.newURI(document.baseURI, null, null),
+            Services.io.newURI('about:blank'/*document.baseURI*/, null, null),
             document.documentElement
         ));
     };