diff --git a/wagtail/admin/rich_text/converters/html_ruleset.py b/wagtail/admin/rich_text/converters/html_ruleset.py
index 6e97229d1a..48d5d401ef 100644
--- a/wagtail/admin/rich_text/converters/html_ruleset.py
+++ b/wagtail/admin/rich_text/converters/html_ruleset.py
@@ -1,5 +1,5 @@
 import re
-from collections import Mapping
+from collections.abc import Mapping
 
 ELEMENT_SELECTOR = re.compile(r'^([\w-]+)$')
 ELEMENT_WITH_ATTR_SELECTOR = re.compile(r'^([\w-]+)\[([\w-]+)\]$')