Investigate how to build PDF logs faster

[akerbos]

Building PDF logs is kind of slow.

1. Are lualatex or pdflatex faster?
2. Is plain TeX faster?
3. Should we drop the error-link-arrows and make do with one engine run for the log?

[koppor]

Workaround: Generate markdown and use grip to render markdown in the browser. Drawback: GitHub knows the error locks as grip uses server-side markdown rendering.

[reitzig]

One can also use Pandoc locally to that end. On GNU/Linux, entr can be used to watch for the log file to change and re-run Pandoc to generate an HTML, which the browser can be configured to auto-refresh on changes (e.g. with Auto Reload in Firefox).