Upgrade Foreman 1.7.x -> 1.8.1, now Foreman wants to remove all of our environments

Hi all,

We upgraded from Foreman 1.7.x to 1.8.1 yesterday.

Today, I attempted to import some new classes by browing to "Configure:
Puppet Classes" and clicking on the "Import from foreman.example.org"
button. Once i do that, Foreman switches me to the URL
"https://foreman.example.org/puppetclasses/import_environments?proxy=1-foreman-example-org",
and under "Select the changes you want to realize in Foreman:", Foreman
says it will remove all 7 of our environments. It says things like this:

Environment Operation Puppet Modules
user1 Remove: Deleted environment
user2 Remove: Deleted environment
production Remove: class1, class2, class3…

We must have done something incorrect during the upgrade. Our
environmentpath is set to the default (/etc/puppet/environments), and
all of our environments can be found under /etc/puppet/environments .

How can I debug this?

-= Stefan