Add highlighting to lines in markdown editor in block code

[oim37]

Hello,

I read manual about markdown code block and not find option where i can highlight lines in code block.

1. To add content in code block i use

In second example lines marked, after save and close it's ok, but when i open post to edit some text < automaticly changed to left quote and not showing part of content.
And when there are a lot of left quotes, they are all converted from &lt; to < and i need to change everything again manually.

In the first example, it considers them as code and displays them as needed, but I cannot select lines there. Asterisks and other attempts to highlight a line did not work for me.

I want something like this:

I searching and find this, as i understand this 3rd party uses by Winter CMS:
i think it what i need thephpleague/commonmark#631 but i don't understand how make it and it some years ago is it actual or no..

Maybe someone has already encountered this and there is a convenient solution, since I don’t want to change markdown editor, overall I really liked it and found it comfortable except for this moment.

[LukeTowers]

@bennothommo would you be willing to take a look at this?