diff --git a/Lib/html/parser.py b/Lib/html/parser.py
index 80fb8c3f929f6b..38ddf9ef442d36 100644
--- a/Lib/html/parser.py
+++ b/Lib/html/parser.py
@@ -387,9 +387,11 @@ def parse_html_declaration(self, i):
def parse_comment(self, i, report=True):
rawdata = self.rawdata
assert rawdata.startswith('" or "--!>" close.
+ match = commentabruptclose.match(rawdata, i+4)
if not match:
- match = commentabruptclose.match(rawdata, i+4)
+ match = commentclose.search(rawdata, i+4)
if not match:
return -1
if report:
diff --git a/Lib/test/test_htmlparser.py b/Lib/test/test_htmlparser.py
index e4eff1ea17a670..6b7624f11505d9 100644
--- a/Lib/test/test_htmlparser.py
+++ b/Lib/test/test_htmlparser.py
@@ -116,6 +116,11 @@ def _run_check(self, source, expected_events,
*, collector=None, convert_charrefs=False):
if collector is None:
collector = self.get_collector(convert_charrefs=convert_charrefs)
+ if isinstance(source, str):
+ # Also feed the whole string at once, not just character by
+ # character (below), to exercise different input buffering.
+ self._run_check([source], expected_events,
+ convert_charrefs=convert_charrefs)
parser = collector
for s in source:
parser.feed(s)
@@ -593,6 +598,9 @@ def test_comments(self):
' -->'
''
''
+ # abruptly closed empty comment must not swallow later text
+ 'x-->'
+ 'y-->'
)
expected = [('comment', " I'm a valid comment "),
('comment', 'me too!'),
@@ -613,6 +621,8 @@ def test_comments(self):
('comment', ' '),
('comment', ''),
+ ('comment', ''), ('data', 'y-->'),
]
self._run_check(html, expected)
diff --git a/Misc/NEWS.d/next/Library/2026-07-04-13-00-00.gh-issue-135661.CIkADG.rst b/Misc/NEWS.d/next/Library/2026-07-04-13-00-00.gh-issue-135661.CIkADG.rst
new file mode 100644
index 00000000000000..26a912a6f3a194
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2026-07-04-13-00-00.gh-issue-135661.CIkADG.rst
@@ -0,0 +1,3 @@
+Fix :class:`html.parser.HTMLParser`: an abruptly closed empty comment
+(```` or ````) no longer extends up to a later ``-->`` in the same
+:meth:`~html.parser.HTMLParser.feed` call.