From 74f679e8bd07530191aba4a211421abc49a9dcd1 Mon Sep 17 00:00:00 2001
From: Sajal Garg <sajal.g@browserstack.com>
Date: Wed, 14 Jan 2026 17:25:33 +0530
Subject: [PATCH 1/4] Added Error Handler

---
 lib/core/utils/performance-timer.js | 29 +++++++++++++++++++----------
 1 file changed, 19 insertions(+), 10 deletions(-)

diff --git a/lib/core/utils/performance-timer.js b/lib/core/utils/performance-timer.js
index 5b26c858..62d3db9f 100644
--- a/lib/core/utils/performance-timer.js
+++ b/lib/core/utils/performance-timer.js
@@ -73,17 +73,26 @@ const performanceTimer = (() => {
      * @param {String} endMark String name of mark to end measuring
      */
     measure(measureName, startMark, endMark, details = {}) {
-      if (window.performance && window.performance.measure !== undefined) {
-        if (Object.keys(details).length > 0) {
-          const measureOpts = {
-            detail: details,
-            start: startMark,
-            end: endMark
-          };
-          window.performance.measure(measureName, measureOpts);
-        } else {
-          window.performance.measure(measureName, startMark, endMark);
+      try {
+        if (window.performance && window.performance.measure !== undefined) {
+          if (Object.keys(details).length > 0) {
+            const measureOpts = {
+              detail: details,
+              start: startMark,
+              end: endMark
+            };
+            window.performance.measure(measureName, measureOpts);
+          } else {
+            window.performance.measure(measureName, startMark, endMark);
+          }
         }
+      } catch (err) {
+        // NOTE: Performance metrics will be missed if an error occurs here
+        a11yEngine.errorHandler.addNonCheckError(
+          'INSTRUMENTATION_ERROR',
+          'AxeCore PerformanceTimer measure Error',
+          err
+        );
       }
     },
     /**

From 389078fd38bdb350b6ab6e4324db1b1c6420d39f Mon Sep 17 00:00:00 2001
From: Sajal Garg <sajal.g@browserstack.com>
Date: Wed, 14 Jan 2026 18:46:38 +0530
Subject: [PATCH 2/4] Fix EDS event error

---
 lib/core/utils/performance-timer.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/core/utils/performance-timer.js b/lib/core/utils/performance-timer.js
index 62d3db9f..1ee71a2b 100644
--- a/lib/core/utils/performance-timer.js
+++ b/lib/core/utils/performance-timer.js
@@ -91,7 +91,8 @@ const performanceTimer = (() => {
         a11yEngine.errorHandler.addNonCheckError(
           'INSTRUMENTATION_ERROR',
           'AxeCore PerformanceTimer measure Error',
-          err
+          err,
+          true
         );
       }
     },

From aa6d83787a0e92d709bc0bcb19ca752627a8a73e Mon Sep 17 00:00:00 2001
From: Sajal Garg <sajal.g@browserstack.com>
Date: Thu, 15 Jan 2026 10:33:14 +0530
Subject: [PATCH 3/4] Updated constants.js with serializableErrorProps

---
 lib/core/constants.js | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/lib/core/constants.js b/lib/core/constants.js
index 71918e37..dec74111 100644
--- a/lib/core/constants.js
+++ b/lib/core/constants.js
@@ -44,7 +44,15 @@ const constants = {
     timeout: 10000
   }),
   allOrigins: '<unsafe_all_origins>',
-  sameOrigin: '<same_origin>'
+  sameOrigin: '<same_origin>',
+  serializableErrorProps: Object.freeze([
+    'message',
+    'stack',
+    'name',
+    'code',
+    'ruleId',
+    'method'
+  ])
 };
 
 definitions.forEach(definition => {

From 0036065647ad9205b7df15a3ef2f433d5591c9dd Mon Sep 17 00:00:00 2001
From: Sajal Garg <sajal.g@browserstack.com>
Date: Thu, 15 Jan 2026 10:37:16 +0530
Subject: [PATCH 4/4] Kept comments same for consistency

---
 lib/core/constants.js | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/lib/core/constants.js b/lib/core/constants.js
index dec74111..c5b9fd2b 100644
--- a/lib/core/constants.js
+++ b/lib/core/constants.js
@@ -27,7 +27,10 @@ const definitions = [
 
 const constants = {
   helpUrlBase: 'https://dequeuniversity.com/rules/',
+  // Size of a grid square in pixels
   gridSize: 200,
+  // At a certain point, looping over an array of elements and using .match on them
+  // is slower than just running querySelectorAll again.
   selectorSimilarFilterLimit: 700,
   results: [],
   resultGroups: [],