reStructuredText markup broken for Robot Framework code blocks

[mentalisttraceur]

Describe the bug
Project description written in reStructuredText; .. code:: robotframework blocks rendered with strikethrough on all the keyword arguments.

Example image from robotframework-dependencylibrary.

Expected behavior
No strikethrough in code blocks.

To Reproduce
Make a package with a reStructuredText description containing .. code:: robotframework blocks with at least one test calling at least one keyword with at least one argument, I presume.

[mentalisttraceur]

I'm pretty sure it has previously rendered correctly for years.

I've had that package with a lot of the same project description reStructuredText since December 2017, last looked at it around October 2021, and I think I would've noticed strikethrough in my code blocks.

[mentalisttraceur]

The change to the generated HTML happened sometime between January 28 2022 and October 31 2022.

Note that my package didn't change between those two dates - it was version 3.0.1 both before and after.

In fact, if you go back to older package versions, you'll see that the rendering of every single release's description has been affected.

[mentalisttraceur]

Looks like the HTML change was specifically <span class='s'>...</span> being replaced with <s>...</s>.

[miketheman]

Thanks for the detailed report! I believe this is due to how the conversion from HTML4 to HTML5 elements worked along with the Pygments library setting for using short codes where 's' is used for a string, and it can also mean strike through.

Fixing this means a change to readme_renderer and the CSS here in warehouse to adapt.