I ran into the same issue and found that, at least for me, the problem seems to have been caused by the current "force" (factorio's concept of a team basically) having been changed. For me it was set to EE_TESTFORCE_1 (maybe something from the editor extensions mod?), changing it back to player solved the problem.
This can be checked and changed through Map Editor -> Tools -> Forces (red flag icon) -> Edit force -> current force dropdown.
Hopefully this might help if anyone else runs into it.