asciio is the true answer :) In fact I love using pure ASCII diagram in my emails, text memos, etc :) https://metacpan.org/pod/App::Asciio https://metacpan.org

asciio is the true answer :) In fact I love using pure ASCII diagram in my emails, text memos, etc :) https://metacpan.org/pod/App::Asciio https://metacpan.org/pod/App::Asciio As it's not completely obvious, Asciio will save to plain text if you simply use the .txt extension, and else its own binary editable format. Asciio is present in Debian/Ubuntu repositories.