diff --git a/src/js/contentscript.js b/src/js/contentscript.js
index 1b8d32ff2..f7c62bd7d 100644
--- a/src/js/contentscript.js
+++ b/src/js/contentscript.js
@@ -366,6 +366,19 @@ var domFilterer = {
         }
     },
 
+    addStyleTag: function(text) {
+        var styleTag = document.createElement('style');
+        styleTag.setAttribute('type', 'text/css');
+        styleTag.textContent = text;
+        if ( document.head ) {
+            document.head.appendChild(styleTag);
+        }
+        this.styleTags.push(styleTag);
+        if ( userCSS ) {
+            userCSS.add(text);
+        }
+    },
+
     checkStyleTags_: function() {
         var doc = document,
             html = doc.documentElement,
@@ -422,16 +435,7 @@ var domFilterer = {
         }
 
         if ( styleText !== '' ) {
-            var styleTag = document.createElement('style');
-            styleTag.setAttribute('type', 'text/css');
-            styleTag.textContent = styleText;
-            if ( document.head ) {
-                document.head.appendChild(styleTag);
-            }
-            this.styleTags.push(styleTag);
-            if ( userCSS ) {
-                userCSS.add(styleText);
-            }
+            this.addStyleTag(styleText);
         }
 
         // Simple selectors: incremental.
@@ -462,8 +466,15 @@ var domFilterer = {
             this.runJob(this.jobQueue[i], complexHideNode);
         }
 
+        // https://github.com/gorhill/uBlock/issues/1912
+        //   If one or more nodes have been manually hidden, insert a style tag
+        //   targeting these manually hidden nodes. For browsers supporting
+        //   user styles, this allows uBO to win.
         var commitHit = this.hiddenNodeCount !== beforeHiddenNodeCount;
         if ( commitHit ) {
+            if ( beforeHiddenNodeCount === 0 ) {
+                this.addStyleTag(':root *[' + this.hiddenId + '][hidden] { display: none !important; }');
+            }
             this.addedNodesHandlerMissCount = 0;
         } else {
             this.addedNodesHandlerMissCount += 1;