Problem with converting on Pop!_OS 20.04 LTS

[MatsuMarucin]

System: Pop!_OS 20.04 LTS
I try to test "mmdless" and during installation saw:

Successfully installed mdless-1.0.14
invalid options: -ri
(invalid options are ignored)
Parsing documentation for mdless-1.0.14
Installing ri documentation for mdless-1.0.14
Done installing documentation for mdless after 0 seconds
1 gem installed

(before I had to install ruby)

But than:

$ mdless Vim.md 

^CTraceback (most recent call last):
	8: from /usr/local/bin/mdless:23:in `<main>'
	7: from /usr/local/bin/mdless:23:in `load'
	6: from /var/lib/gems/2.7.0/gems/mdless-1.0.14/bin/mdless:17:in `<top (required)>'
	5: from /var/lib/gems/2.7.0/gems/mdless-1.0.14/bin/mdless:17:in `new'
	4: from /var/lib/gems/2.7.0/gems/mdless-1.0.14/lib/mdless/converter.rb:121:in `initialize'
	3: from /var/lib/gems/2.7.0/gems/mdless-1.0.14/lib/mdless/converter.rb:121:in `each'
	2: from /var/lib/gems/2.7.0/gems/mdless-1.0.14/lib/mdless/converter.rb:134:in `block in initialize'
	1: from /var/lib/gems/2.7.0/gems/mdless-1.0.14/lib/mdless/converter.rb:578:in `convert_markdown'
/var/lib/gems/2.7.0/gems/mdless-1.0.14/lib/mdless/converter.rb:578:in `gsub!': Interrupt

What do i wrong ?