Unusual checkouts are deferred with a plain reason and advice to use the main clone.
What's wrong with this entry?
A new refusal reason covers checkouts that are linked working trees or keep their git directory elsewhere. Those sessions are deferred instead of probed, get their own preface saying nothing syncs back and the session cannot push to GitHub, and the remedy suggests starting from the repository's main checkout or an ordinary clone.
- The reason is recorded as
layout_unserved.
start from the repository's main checkout
Strings lifted out of the shipped bundle, so the claim above can be checked against them.