diff --git a/src/rules.ts b/src/rules.ts
index 67dcb09ece..e661bee4a3 100644
--- a/src/rules.ts
+++ b/src/rules.ts
@@ -408,12 +408,15 @@ const inlineGfm: Record<InlineKeys, RegExp> = {
   ...inlineNormal,
   emStrongRDelimAst: emStrongRDelimAstGfm,
   emStrongLDelim: emStrongLDelimGfm,
-  url: edit(/^((?:ftp|https?):\/\/|www\.)(?:[a-zA-Z0-9\-]+\.?)+[^\s<]*|^email/, 'i')
+  url: edit(/^((?:protocol):\/\/|www\.)(?:[a-zA-Z0-9\-]+\.?)+[^\s<]*|^email/)
+    .replace('protocol', /[fF][tT][pP]|[hH][tT][tT][pP][sS]?/)
     .replace('email', /[A-Za-z0-9._+-]+(@)[a-zA-Z0-9-_]+(?:\.[a-zA-Z0-9-_]*[a-zA-Z0-9])+(?![-_])/)
     .getRegex(),
   _backpedal: /(?:[^?!.,:;*_'"~()&]+|\([^)]*\)|&(?![a-zA-Z0-9]+;$)|[?!.,:;*_'"~)]+(?!$))+/,
   del: /^(~~?)(?=[^\s~])((?:\\[\s\S]|[^\\])*?(?:\\[\s\S]|[^\s~\\]))\1(?=[^~]|$)/,
-  text: /^([`~]+|[^`~])(?:(?= {2,}\n)|(?=[a-zA-Z0-9.!#$%&'*+\/=?_`{\|}~-]+@)|[\s\S]*?(?:(?=[\\<!\[`*~_]|\b_|https?:\/\/|ftp:\/\/|www\.|$)|[^ ](?= {2,}\n)|[^a-zA-Z0-9.!#$%&'*+\/=?_`{\|}~-](?=[a-zA-Z0-9.!#$%&'*+\/=?_`{\|}~-]+@)))/,
+  text: edit(/^([`~]+|[^`~])(?:(?= {2,}\n)|(?=[a-zA-Z0-9.!#$%&'*+\/=?_`{\|}~-]+@)|[\s\S]*?(?:(?=[\\<!\[`*~_]|\b_|protocol:\/\/|www\.|$)|[^ ](?= {2,}\n)|[^a-zA-Z0-9.!#$%&'*+\/=?_`{\|}~-](?=[a-zA-Z0-9.!#$%&'*+\/=?_`{\|}~-]+@)))/)
+    .replace('protocol', /[hH][tT][tT][pP][sS]?|[fF][tT][pP]/)
+    .getRegex(),
 };
 
 /**
diff --git a/test/specs/new/autolinks.html b/test/specs/new/autolinks.html
index 8fa4837e61..bc0fbc0546 100644
--- a/test/specs/new/autolinks.html
+++ b/test/specs/new/autolinks.html
@@ -12,4 +12,12 @@
 
 <p><strong><a href="mailto:me@example.com">me@example.com</a></strong></p>
 
-<p><strong><a href="mailto:test@test.com">test@test.com</a></strong></p>
\ No newline at end of file
+<p><strong><a href="mailto:test@test.com">test@test.com</a></strong></p>
+
+<p><a href="http://www.example.com">www.example.com</a></p>
+
+<p>Www.example.com</p>
+
+<p>WWW.example.com</p>
+
+<p>(See <a href="hTtPS://example.com/fhqwhgads">hTtPS://example.com/fhqwhgads</a>.)</p>
diff --git a/test/specs/new/autolinks.md b/test/specs/new/autolinks.md
index 1f5f739c49..e5e41fd761 100644
--- a/test/specs/new/autolinks.md
+++ b/test/specs/new/autolinks.md
@@ -12,4 +12,12 @@ hTtP://fOo.CoM
 
 **me@example.com**
 
-__test@test.com__
\ No newline at end of file
+__test@test.com__
+
+www.example.com
+
+Www.example.com
+
+WWW.example.com
+
+(See hTtPS://example.com/fhqwhgads.)