Facebook error when linking DTube account

[AbakumovAlexandr]

I am creating a DTube account and choose to link it with Facebook. I am successfully logged into my Facebook account on another browser's tab already.

When clicking on the red 'Link' button, I am getting redirected to a FB OAuth page and immediately getting an error:

After like 5 of attempts to link the accounts all resulted in the error above, my account got disabled by FB:

Has DTibe's FB OAuth token (or how is it called?) expired or is it a bug in DTube app?