install koreader on RM 2 version 3.9

[sife33]

hi everyone
first I'M new here and I'm sorry for my English
my request is that I wanna install koreader in my remarkable 2 which have Version 3.9
I dont konw if this is possible ; i think I can't do it without tolec after version 2.15
note : I'm not a programmer I just know basics things about computer that's why I hope there are some steps which I need just use ssh commend to
install it
thanks in advance

[Eeems]

https://remarkable.guide/faqs.html#can-i-downgrade-to-a-different-os-version