Support for the Ruby 2.4 series has ended. See here for reference.
Raised when there are conflicting gem specs loaded
# File rubygems/errors.rb, line 81 def initialize target, conflicts @target = target @conflicts = conflicts @name = target.name reason = conflicts.map { |act, dependencies| "#{act.full_name} conflicts with #{dependencies.join(", ")}" }.join ", " # TODO: improve message by saying who activated `con` super("Unable to activate #{target.full_name}, because #{reason}") end