I changed the name of a custom post type after seeing it appear twice in dropdowns.
It was "Feed Items." After seeing it twice in dropdowns, I changed its name to Feed Articles... and I still see "Feed Items"
I visited this URL:
I expected to see: No more listing of "Feed Items"
Instead, I got: it's still there, along with the new name.
Seeing it twice in the dropdowns shouldn't happen in the first place. In your debug info I can see your registered post types and it shows only Feed Articles and not Feed Items.
I suspect a conflict with another plugin may be responsible. Can we first eliminate that possibility?
Disable all of your non-Toolset plugins and then re-check. If it is a plugin conflict you can re-enable them one-by-one or in batches to track down which.
Similarly, can you test your theme by switching to twentyseventeen and re-testing.
It's WP RSS Aggregator... it had already created that CPT, it seems. Deactivating it causes the duplicate to disappear.
So, I'll use the Types CPT and just avoid the other..:)
This ticket is now closed. If you're a Toolset client and need related help, please open a new support ticket.