ActionController::InvalidAuthenticityToken on all rails apps?

Question

Ruby on Rails

Hey! On all Rails sites (not even mine), ActionController::InvalidAuthenticityToken pops up in all my browsers.
At first I thought I broke something while developing my site. But no, I looked into the rails sample apps and saw the same error. Opened another browser. It happened again.
What the hell is going on? Has anyone come across?

Answer 1

It turned out that I had set tld_length: 2 and the local copy was on localhost. Solved by redirecting site.local domain to 127.0.0.1

Answer 2

Here is a similar problem, solved by replacing application_controller.rb
with
protect_from_forgery with: :null_session

Answer 3

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