diff --git a/demo/markdownlint-browser.js b/demo/markdownlint-browser.js
index c2915315..ef973fbe 100644
--- a/demo/markdownlint-browser.js
+++ b/demo/markdownlint-browser.js
@@ -1350,14 +1350,12 @@ function lintContent(ruleList, name, content, md, config, frontMatter, handleRul
     // eslint-disable-next-line jsdoc/require-jsdoc
     function forRule(rule) {
         // Configure rule
-        var ruleNameFriendly = rule.names[0];
-        var ruleName = ruleNameFriendly.toUpperCase();
+        var ruleName = rule.names[0].toUpperCase();
         params.config = effectiveConfig[ruleName];
         // eslint-disable-next-line jsdoc/require-jsdoc
         function throwError(property) {
             throw new Error("Property '" + property + "' of onError parameter is incorrect.");
         }
-        var errors = [];
         // eslint-disable-next-line jsdoc/require-jsdoc
         function onError(errorInfo) {
             if (!errorInfo ||
@@ -1366,6 +1364,10 @@ function lintContent(ruleList, name, content, md, config, frontMatter, handleRul
                 (errorInfo.lineNumber > lines.length)) {
                 throwError("lineNumber");
             }
+            var lineNumber = errorInfo.lineNumber + frontMatterLines.length;
+            if (!enabledRulesPerLineNumber[lineNumber][ruleName]) {
+                return;
+            }
             if (errorInfo.detail &&
                 !helpers.isString(errorInfo.detail)) {
                 throwError("detail");
@@ -1426,11 +1428,15 @@ function lintContent(ruleList, name, content, md, config, frontMatter, handleRul
                     cleanFixInfo.insertText = fixInfo.insertText;
                 }
             }
-            errors.push({
-                "lineNumber": errorInfo.lineNumber + frontMatterLines.length,
-                "detail": errorInfo.detail || null,
-                "context": errorInfo.context || null,
-                "range": errorInfo.range ? __spreadArray([], errorInfo.range) : null,
+            results.push({
+                lineNumber: lineNumber,
+                "ruleName": rule.names[0],
+                "ruleNames": rule.names,
+                "ruleDescription": rule.description,
+                "ruleInformation": rule.information ? rule.information.href : null,
+                "errorDetail": errorInfo.detail || null,
+                "errorContext": errorInfo.context || null,
+                "errorRange": errorInfo.range ? __spreadArray([], errorInfo.range) : null,
                 "fixInfo": fixInfo ? cleanFixInfo : null
             });
         }
@@ -1449,23 +1455,6 @@ function lintContent(ruleList, name, content, md, config, frontMatter, handleRul
         else {
             rule.function(params, onError);
         }
-        // Record any errors (significant performance benefit from length check)
-        if (errors.length > 0) {
-            var filteredErrors = errors
-                .filter(function (error) { return (enabledRulesPerLineNumber[error.lineNumber][ruleName]); })
-                .map(function (error) { return ({
-                "lineNumber": error.lineNumber,
-                "ruleName": rule.names[0],
-                "ruleNames": rule.names,
-                "ruleDescription": rule.description,
-                "ruleInformation": rule.information ? rule.information.href : null,
-                "errorDetail": error.detail,
-                "errorContext": error.context,
-                "errorRange": error.range,
-                "fixInfo": error.fixInfo
-            }); });
-            Array.prototype.push.apply(results, filteredErrors);
-        }
     }
     // Run all rules
     try {
diff --git a/lib/markdownlint.js b/lib/markdownlint.js
index 7c4554d1..0f841cb8 100644
--- a/lib/markdownlint.js
+++ b/lib/markdownlint.js
@@ -480,15 +480,13 @@ function lintContent(
   // eslint-disable-next-line jsdoc/require-jsdoc
   function forRule(rule) {
     // Configure rule
-    const ruleNameFriendly = rule.names[0];
-    const ruleName = ruleNameFriendly.toUpperCase();
+    const ruleName = rule.names[0].toUpperCase();
     params.config = effectiveConfig[ruleName];
     // eslint-disable-next-line jsdoc/require-jsdoc
     function throwError(property) {
       throw new Error(
         "Property '" + property + "' of onError parameter is incorrect.");
     }
-    const errors = [];
     // eslint-disable-next-line jsdoc/require-jsdoc
     function onError(errorInfo) {
       if (!errorInfo ||
@@ -497,6 +495,10 @@ function lintContent(
         (errorInfo.lineNumber > lines.length)) {
         throwError("lineNumber");
       }
+      const lineNumber = errorInfo.lineNumber + frontMatterLines.length;
+      if (!enabledRulesPerLineNumber[lineNumber][ruleName]) {
+        return;
+      }
       if (errorInfo.detail &&
         !helpers.isString(errorInfo.detail)) {
         throwError("detail");
@@ -557,11 +559,15 @@ function lintContent(
           cleanFixInfo.insertText = fixInfo.insertText;
         }
       }
-      errors.push({
-        "lineNumber": errorInfo.lineNumber + frontMatterLines.length,
-        "detail": errorInfo.detail || null,
-        "context": errorInfo.context || null,
-        "range": errorInfo.range ? [ ...errorInfo.range ] : null,
+      results.push({
+        lineNumber,
+        "ruleName": rule.names[0],
+        "ruleNames": rule.names,
+        "ruleDescription": rule.description,
+        "ruleInformation": rule.information ? rule.information.href : null,
+        "errorDetail": errorInfo.detail || null,
+        "errorContext": errorInfo.context || null,
+        "errorRange": errorInfo.range ? [ ...errorInfo.range ] : null,
         "fixInfo": fixInfo ? cleanFixInfo : null
       });
     }
@@ -578,25 +584,6 @@ function lintContent(
     } else {
       rule.function(params, onError);
     }
-    // Record any errors (significant performance benefit from length check)
-    if (errors.length > 0) {
-      const filteredErrors = errors
-        .filter((error) => (
-          enabledRulesPerLineNumber[error.lineNumber][ruleName]
-        ))
-        .map((error) => ({
-          "lineNumber": error.lineNumber,
-          "ruleName": rule.names[0],
-          "ruleNames": rule.names,
-          "ruleDescription": rule.description,
-          "ruleInformation": rule.information ? rule.information.href : null,
-          "errorDetail": error.detail,
-          "errorContext": error.context,
-          "errorRange": error.range,
-          "fixInfo": error.fixInfo
-        }));
-      Array.prototype.push.apply(results, filteredErrors);
-    }
   }
   // Run all rules
   try {