Tabs do not work in the pdf version

[rantahar]

The materials include code sections with tabs. These are rendeder statically in the pdf version (https://coderefinery.github.io/documentation/lesson.pdf).

• Including imgmath in pdf generation causes the tabs to expand, but without any formatting. This is a bug.

How should the tabs be rendered? Would we want all of them one after another, or separate pdfs for each tabgroup name? Do we want

• lesson_C.pdf
• lesson_R.pdf
• lesson_julia.pdf
• ...

Or do we want a single pdf with all the examples?