diff -r a736ab681b78 -r d2e1dcd4490d mercurial/hgweb/hgweb_mod.py
--- a/mercurial/hgweb/hgweb_mod.py	Thu Oct 08 15:35:44 2020 -0700
+++ b/mercurial/hgweb/hgweb_mod.py	Thu Oct 08 13:37:31 2020 -0700
@@ -493,7 +493,7 @@
         except error.Abort as e:
             res.status = b'403 Forbidden'
             res.headers[b'Content-Type'] = ctype
-            return rctx.sendtemplate(b'error', error=pycompat.bytestr(e))
+            return rctx.sendtemplate(b'error', error=e.message)
         except ErrorResponse as e:
             for k, v in e.headers:
                 res.headers[k] = v