diff --git a/app/src/main/java/com/trianguloy/urlchecker/modules/list/PatternModule.java b/app/src/main/java/com/trianguloy/urlchecker/modules/list/PatternModule.java
index b8db4de..eb9f73a 100644
--- a/app/src/main/java/com/trianguloy/urlchecker/modules/list/PatternModule.java
+++ b/app/src/main/java/com/trianguloy/urlchecker/modules/list/PatternModule.java
@@ -74,6 +74,7 @@ class PatternConfig extends AModuleConfig {
                         R.string.mPttrn_userContent,
                         "https://github.com/TrianguloY/UrlChecker/wiki/Custom-patterns"
                 ));
+        RegexFix.attachSetting(views.findViewById(R.id.regex_fix));
     }
 
 }
@@ -85,12 +86,14 @@ class PatternDialog extends AModuleDialog {
     private LinearLayout box;
 
     private final PatternCatalog catalog;
+    private final RegexFix regexFix;
 
     private final List<Message> messages = new ArrayList<>();
 
     public PatternDialog(MainDialog dialog) {
         super(dialog);
         catalog = new PatternCatalog(dialog);
+        regexFix = new RegexFix(dialog);
     }
 
     @Override
@@ -159,7 +162,7 @@ class PatternDialog extends AModuleDialog {
 
                     if (replacement != null) {
                         // replace url
-                        message.newUrl = RegexFix.replaceAll(url, regex, replacement);
+                        message.newUrl = regexFix.replaceAll(url, regex, replacement);
 
                         // automatic? apply
                         if (data.optBoolean("automatic")) {
diff --git a/app/src/main/java/com/trianguloy/urlchecker/utilities/RegexFix.java b/app/src/main/java/com/trianguloy/urlchecker/utilities/RegexFix.java
index ee47144..f7ab804 100644
--- a/app/src/main/java/com/trianguloy/urlchecker/utilities/RegexFix.java
+++ b/app/src/main/java/com/trianguloy/urlchecker/utilities/RegexFix.java
@@ -1,23 +1,58 @@
 package com.trianguloy.urlchecker.utilities;
 
-import android.annotation.TargetApi;
+import android.content.Context;
 import android.os.Build;
+import android.view.View;
+import android.widget.Switch;
 
-import java.util.regex.Pattern;
 import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+/**
+ * On Android 10 and under, optional groups may yield a "null" in the replacement output instead of an empty string.
+ * Therefore, we just copy the implementation from a newer version of Android
+ * https://github.com/TrianguloY/UrlChecker/issues/237
+ */
+public class RegexFix {
 
-public interface RegexFix {
     /**
-     * On Android 10 and under, optional groups may yield a "null" in the replacement output instead of an empty string.
-     * Therefore, we just copy the implementation from a newer version of Android
-     * https://github.com/TrianguloY/UrlChecker/issues/237
+     * Android 11 and up have already the fix, disable in those cases
      */
-    static String replaceAll(String text, Pattern pattern, String replacement) {
-        // Copied from https://android.googlesource.com/platform/libcore/+/refs/heads/android13-release/ojluni/src/main/java/java/util/regex/Matcher.java#837
+    public static final boolean IS_ANDROID_FIXED = Build.VERSION.SDK_INT >= Build.VERSION_CODES.R;
+
+    private final GenericPref.Bool pttrn_regexfix;
+
+    public RegexFix(Context cntx) {
+        // fix enabled by default
+        pttrn_regexfix = new GenericPref.Bool("pttrn_regexfix", true, cntx);
+    }
+
+    /**
+     * Attach the setting to a given switch view (or disabled if not needed)
+     */
+    public static void attachSetting(Switch view) {
+        if (IS_ANDROID_FIXED) {
+            // hide, already native
+            view.setVisibility(View.GONE);
+        } else {
+            // show, required
+            new RegexFix(view.getContext()).pttrn_regexfix.attachToSwitch(view);
+            view.setVisibility(View.VISIBLE);
+        }
+    }
+
+    /**
+     * Use this instead of: pattern.matcher(text).replaceAll(replacement)
+     */
+    public String replaceAll(String text, Pattern pattern, String replacement) {
         Matcher matcher = pattern.matcher(text);
-        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.R) {
+
+        if (IS_ANDROID_FIXED || !pttrn_regexfix.get()) {
+            // no fix required or explicitly disabled, just use native function
             return matcher.replaceAll(replacement);
         }
+
+        // Copied from https://android.googlesource.com/platform/libcore/+/refs/heads/android13-release/ojluni/src/main/java/java/util/regex/Matcher.java#837
         boolean result = matcher.find();
         if (result) {
             StringBuffer sb = new StringBuffer();
@@ -36,12 +71,9 @@ public interface RegexFix {
         // Copied from https://android.googlesource.com/platform/libcore/+/refs/heads/android13-release/ojluni/src/main/java/java/util/regex/Matcher.java#714
         sb.append(text.substring(appendPos, matcher.start()));
         appendEvaluated(matcher, sb, replacement);
-        int newAppendPos = matcher.end();
-
-        return newAppendPos;
+        return matcher.end();
     }
 
-    @TargetApi(Build.VERSION_CODES.O)
     private static void appendEvaluated(Matcher matcher, StringBuffer buffer, String s) {
         // Copied from https://android.googlesource.com/platform/libcore/+/refs/heads/android13-release/ojluni/src/main/java/java/util/regex/Matcher.java#731
         boolean escape = false;
diff --git a/app/src/main/res/layout/config_patterns.xml b/app/src/main/res/layout/config_patterns.xml
index 7d20649..d359d21 100644
--- a/app/src/main/res/layout/config_patterns.xml
+++ b/app/src/main/res/layout/config_patterns.xml
@@ -16,6 +16,12 @@
         android:layout_height="wrap_content"
         android:text="@string/json_edit" />
 
+    <Switch
+        android:id="@+id/regex_fix"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:text="@string/mPttrn_regexfix" />
+
     <TextView
         android:id="@+id/user_content"
         android:layout_width="match_parent"
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 23b831e..153e05d 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -119,6 +119,7 @@ Built-in patterns include:
 - Warning when contains non-ascii characters like greek letters. This can be used for phishing: googĺe.com vs google.com
 - Suggest replacing 'http' with 'https'
 - Suggest replacing Youtube, Reddit or Twitter with privacy-friendly alternatives [disabled by default]"</string>
+    <string name="mPttrn_regexfix">Fix optional regex groups (disable if regex is not working correctly)</string>
     <string name="mPttrn_userContent">List of other useful user-created patterns: %s</string>
     <string name="mPttrn_fix">Apply</string>
     <string name="mPttrn_fixed">Applied - %s</string>