portlint: OK (looks fine.)
testport: OK (poudriere: 10amd64, 11amd64 and 12amd64)
maketest: OK (5 failed, 1965 passed, 36 skipped, 5 xfailed in 42.83 seconds)
The five failed tests are not actually failed -- all of them "fail" as follows:
```
E AssertionError: assert <CIMultiDict(...': 'header2')> == {'h1': 'h1', 'h2': 'header2'}
E Full diff:
E - <CIMultiDict('H1': 'h1', 'h2': 'header2')>
E + {'h1': 'h1', 'h2': 'header2'}
tests/test_client_session.py:153: AssertionError
```
I'm not sure how the <CIMultiDict(> creeps into the output there. The actual output is as expected. I suspect outdated `TEST_DEPENDS`.
I did a run-test with the updated py3-threema-msgapi and everything seems quite happy. It wouldn't be nearly as happy if there was actual brokenness.