Apply suggestions from code review

Co-authored-by: Ezio Melotti <[email protected]>

Author: serhiy-storchaka

Lib/html/parser.py

@@ -401,7 +401,7 @@ def parse_endtag(self, i):
             return -1
         if not endtagopen.match(rawdata, i):  # </ + letter
             # w3.org/TR/html5/tokenization.html#end-tag-open-state
-            if rawdata[i+2:i+3] == '>':
+            if rawdata[i+2:i+3] == '>':  # </> is ignored
                 return i+3
             else:
                 return self.parse_bogus_comment(i)

Misc/NEWS.d/next/Library/2025-06-25-14-13-39.gh-issue-135661.idjQ0B.rst

@@ -1,4 +1,5 @@
-Fix parsing start and end tags in :class:`html.parser.HTMLParser`.
+Fix parsing start and end tags in :class:`html.parser.HTMLParser`
+according to the HTML5 standard.
 
 * Whitespaces no longer accepted between ``</`` and the tag name.
   E.g. ``</ script>`` does not end the script section.
@@ -8,8 +9,9 @@ Fix parsing start and end tags in :class:`html.parser.HTMLParser`.
 
 * Null character (U+0000) no longer ends the tag name.
 
-* End tag can have attributes and slashes after tag name. It no longer ends
-  after the first ``>`` in quoted attribute value. E.g. ``</script/foo=">"/>``.
+* Attributes and slashes after the tag name in end tags are now correctly
+  parsed as comments, instead of terminating after the first ``>``
+  in quoted attribute value. E.g. ``</script/foo=">"/>``.
 
 * Multiple slashes and whitespaces between the last attribute and closing ``>``
   are now accepted in both start and end tags. E.g. ``<a foo=bar/ //>``.