Modules with decomposable characters in module name not found on macOS

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2020-03-03.00:25:16.687>
labels = ['OS-mac', 'interpreter-core', 'type-bug', '3.8']
title = 'Modules with decomposable characters in module name not found on macOS'
updated_at = <Date 2020-03-10.18:09:08.632>
user = 'https://bugs.python.org/Norbert'

bugs.python.org fields:

activity = <Date 2020-03-10.18:09:08.632>
actor = 'brett.cannon'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Interpreter Core', 'macOS']
creation = <Date 2020-03-03.00:25:16.687>
creator = 'Norbert'
dependencies = []
files = ['48944']
hgrepos = []
issue_num = 39832
keywords = []
message_count = 5.0
messages = ['363224', '363614', '363774', '363804', '363836']
nosy_count = 5.0
nosy_names = ['brett.cannon', 'ronaldoussoren', 'vstinner', 'ned.deily', 'Norbert']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue39832'
versions = ['Python 3.8']