Freezable triggers on external objects when using fibers

[utay]

Because thread_mattr_accessor uses Thread.current[], doing self.prevent_instance_data_manipulation_after_freezing = false in the Object extension doesn't work when using fibers (it defaults to true). FWIW discussions in rails/rails#19693 seem related.

In our case we set config.active_support.isolation_level = :fiber in the Rails config.

For instance:

/usr/local/bundle/gems/console1984-0.1.31/lib/console1984/freezeable.rb:42:in `block in prevent_sensitive_method': You can't invoke instance_variable_get on #<ActiveRecord::Reflection::RuntimeReflection:0x00007fb3f5340700> (Console1984::Errors::ForbiddenCommandAttempted)
        from /usr/local/bundle/bundler/gems/activerecord-jsonb-associations-dde23b72bdb7/lib/activerecord/jsonb/associations/association_scope.rb:7:in `last_chain_scope'
        from /usr/local/bundle/gems/activerecord-7.1.3/lib/active_record/associations/association_scope.rb:125:in `add_constraints'
        from /usr/local/bundle/gems/activerecord-7.1.3/lib/active_record/associations/association_scope.rb:29:in `scope'

Any reason to use thread_mattr_accessor in this case versus mattr_accessor?