irb behaves strange in Ruby 2.6
When trying to press the UP, DOWN, LEFT and RIGHT keys in Ruby 2.6 strange characters are printed instead of moving (or showing the last executed instruction). This works properly for me in Ruby 2.5.
Updated by aycabta (aycabta .) almost 3 years ago
The keyboard line editing behaviors are based on GNU Readline. Please install GNU Readline before you build Ruby.
For example, if you're using Ubuntu 18.10, run
sudo apt install libreadline-dev and re-build Ruby.