Issue #20622 has been updated by chmaynard (Craig Maynard). Good advice, thanks. Problem solved by changing the encoding of ~/.inputrc to UTF-8. ---------------------------------------- Bug #20622: irb: invalid byte sequence in UTF-8 https://bugs.ruby-lang.org/issues/20622#change-109090 * Author: chmaynard (Craig Maynard) * Status: Open * ruby -v: ruby 3.3.3 (2024-06-12 revision f1c7b6f435) [arm64-darwin23] * Backport: 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN ---------------------------------------- Ruby $ irb /opt/homebrew/Cellar/ruby/3.3.3/lib/ruby/3.3.0/reline/config.rb:172:in `match': invalid byte sequence in UTF-8 (ArgumentError) next if line.match(/\A\s*#/) ^^^^^^^^ -- https://bugs.ruby-lang.org/