Improvement idea: increase image resolution for Markdown output

[turbanisch]

By default, image files generated with format: gfm from a Quarto/R Markdown file have a much lower resolution than image files generated for HTML output. Is there a specific reason for this behavior or would it make sense to harmonize the two?

When rendering the Markdown output file on github.com, the image is even wider than in an HTML output file so the lower resolution really shows.

---

By filing an issue to this repo, I promise that

• [x] I have fully read the issue guide at https://yihui.org/issue/.
• [ ] I have provided the necessary information about my issue.
  • If I'm asking a question, I have already asked it on Stack Overflow or RStudio Community, waited for at least 24 hours, and included a link to my question there.
  • If I'm filing a bug report, I have included a minimal, self-contained, and reproducible example, and have also included xfun::session_info('knitr'). I have upgraded all my packages to their latest versions (e.g., R, RStudio, and R packages), and also tried the development version: remotes::install_github('yihui/knitr').
  • If I have posted the same issue elsewhere, I have also mentioned it in this issue.
• [x] I have learned the Github Markdown syntax, and formatted my issue correctly.

I understand that my issue may be closed if I don't fulfill my promises.