IDLE revise config-extensions.def comment- only good modules

GitHub fields:

assignee = 'https://github.com/terryjreedy'
closed_at = None
created_at = <Date 2020-03-21.09:42:34.501>
labels = ['expert-IDLE', 'type-bug', '3.8']
title = 'IDLE revise config-extensions.def comment- only good modules'
updated_at = <Date 2020-06-15.22:46:45.193>
user = 'https://bugs.python.org/Vader27'

bugs.python.org fields:

activity = <Date 2020-06-15.22:46:45.193>
actor = 'terry.reedy'
assignee = 'terry.reedy'
closed = False
closed_date = None
closer = None
components = ['IDLE']
creation = <Date 2020-03-21.09:42:34.501>
creator = 'Vader27'
dependencies = []
files = ['49116']
hgrepos = []
issue_num = 40031
keywords = []
message_count = 15.0
messages = ['364735', '364775', '364792', '364796', '364976', '365158', '365159', '367221', '367267', '367269', '367282', '367921', '367945', '367959', '367965']
nosy_count = 4.0
nosy_names = ['terry.reedy', 'taleinat', 'cheryl.sabella', 'Vader27']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue40031'
versions = ['Python 3.8']