Overflow scroll option on codeblocks

Feature requests
1

When using codeblocks, i had this issue happening:

Screenshot from my blog where the lines are overflowing
Screenshot from my blog where the lines are overflowing2520×424 73.7 KB

It was even more prominent on mobile devices, where zooming out the page wouldn’t improve it

I figured out that the way to fix this behaviour is by simply adding a overflow: scroll; to the <pre>'s style attribute. Using this will result in a scrollbar appearing on the bottom of the rendered codeblock, so that the content is always stays within the page

Because i thought some people would like not to have such behaviour, i added it as an option to codeblocks, which is used like this:

```overflowscroll

Note: I have implemented it and will post a PR regarding this topic, which will be linked in the comments

2

I’m not sure why this needs a Zola change? As you say, you can already achieve this sort of thing in your CSS stylesheet, and I assume most people already do.

BTW, I tend to prefer overflow-x: auto; rather than overflow: scroll; You very rarely want vertical scrolling since the page height isn’t usually constrained, and for static content there’s no reason to have scrollbars wasting space when you don’t need them.