diff -r b1e1559f5a45 -r de2e04fe4897 mercurial/configitems.py
--- a/mercurial/configitems.py	Wed Jul 28 13:45:07 2021 +0300
+++ b/mercurial/configitems.py	Tue Jul 20 17:20:19 2021 +0200
@@ -1266,6 +1266,11 @@
 )
 coreconfigitem(
     b'experimental',
+    b'web.full-garbage-collection-rate',
+    default=1,  # still forcing a full collection on each request
+)
+coreconfigitem(
+    b'experimental',
     b'worker.wdir-get-thread-safe',
     default=False,
 )