fix: Fix removetags (ietf-tools#4226)

I don't think this ever worked.

Author: larseggert

ietf/utils/html.py

@@ -34,7 +34,7 @@ def unescape(text):
 def remove_tags(html, tags):
     """Returns the given HTML sanitized, and with the given tags removed."""
     allowed = set(acceptable_tags) - set([ t.lower() for t in tags ])
-    return bleach.clean(html, tags=allowed)
+    return bleach.clean(html, tags=allowed, strip=True)
 
 # ----------------------------------------------------------------------
 # Html fragment cleaning

ietf/utils/templatetags/htmlfilters.py

@@ -1,6 +1,7 @@
 # Copyright The IETF Trust 2017-2020, All Rights Reserved
 # -*- coding: utf-8 -*-
 
+import re
 
 from django.template.library import Library
 from django.template.defaultfilters import stringfilter
@@ -9,9 +10,9 @@
 
 register = Library()
 
+
 @register.filter(is_safe=True)
 @stringfilter
 def removetags(value, tags):
-    """Removes a space separated list of [X]HTML tags from the output."""
-    return remove_tags(value, tags)
-
+    """Removes a comma-separated list of [X]HTML tags from the output."""
+    return remove_tags(value, re.split(r"\s*,\s*", tags))