【Rails】How to settle uninitialized constant ActiveSupport::LoggerThreadSafeLevel::Logger (NameError)

Introduction

Hello everyone.
I'm learning programming by myself in the U.S and trying to become a software engineer.
Before I studied Rails tutorial, I couldn't do 'rails -v' command because of this error 'uninitialized constant ActiveSupport::LoggerThreadSafeLevel::Logger (NameError)'.

Today I'm going to talk about how to settle this problem.

What caused this error?

I ran this command in Jan 16th 2025.

rails new _7.0.4.3_ sample_application

After that, the terminal showed this error when I ran 'rails -v'

uninitialized constant ActiveSupport::LoggerThreadSafeLevel::Logger (NameError)
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I looked for why it caused this error, and it turned out that concurrent-rubygem recently updated to version 1.3.5.

How to fix it

I fixed this bug like this:

1. Add this command to Gemfile

gem 'concurrent-ruby', '1.3.4'

1. run 'bundle install'

To this day(Jan 27th 2025), it remains unresolved.