[] ~/projects/webrick $ echo $FOO
?ۤ?

[] ~/projects/webrick $ rvm ruby-2.6.5 do ruby -v -e 'p ENV["FOO"].bytes'
ruby 2.6.5p114 (2019-10-01 revision 67812) [x86_64-darwin18]
[63, 219, 164, 63]

[] ~/projects/webrick $ ruby -v -e 'p ENV["FOO"].bytes'
jruby 9.3.0.0-SNAPSHOT (2.6.5) 2020-05-27 33f7a3d8d4 OpenJDK 64-Bit Server VM 25.222-b10 on 1.8.0_222-b10 +jit [darwin-x86_64]
[63, 219, 164, 63]