diff --git a/platform/mv3/extension/js/scripting/css-procedural.js b/platform/mv3/extension/js/scripting/css-procedural.js
index 364bd41f4..f8fc6f0a1 100644
--- a/platform/mv3/extension/js/scripting/css-procedural.js
+++ b/platform/mv3/extension/js/scripting/css-procedural.js
@@ -192,7 +192,9 @@ class PSelectorMatchesMediaTask extends PSelectorTask {
 class PSelectorMatchesPathTask extends PSelectorTask {
     constructor(task) {
         super();
-        this.needle = regexFromString(task[1]);
+        this.needle = regexFromString(
+            task[1].replace(/\P{ASCII}/gu, s => encodeURIComponent(s))
+        );
     }
     transpose(node, output) {
         if ( this.needle.test(self.location.pathname + self.location.search) ) {
diff --git a/src/js/contentscript-extra.js b/src/js/contentscript-extra.js
index 344165693..29a736d21 100644
--- a/src/js/contentscript-extra.js
+++ b/src/js/contentscript-extra.js
@@ -161,7 +161,9 @@ class PSelectorMatchesMediaTask extends PSelectorTask {
 class PSelectorMatchesPathTask extends PSelectorTask {
     constructor(task) {
         super();
-        this.needle = regexFromString(task[1]);
+        this.needle = regexFromString(
+            task[1].replace(/\P{ASCII}/gu, s => encodeURIComponent(s))
+        );
     }
     transpose(node, output) {
         if ( this.needle.test(self.location.pathname + self.location.search) ) {