render-on-save: false ignored for ipynb

[memeplex]

Bug description

When previewing a ipynb file in vscode, both render-on-save: false in the metadata and "quarto.render.renderOnSave": false in settings, are ignored. The preview is refreshing each time I save the notebook. This doesn't happen with qmd files.

Steps to reproduce

• Create a notebook
• Add a quarto header
• Set editor: render-on-save: false
• Set "quarto.render.renderOnSave": false in VSCode settings
• Type some text in a markdown cell
• Save

Actual behavior

Preview is refreshed after save.

Expected behavior

Preview is refreshed upon request (e.g. C-S-k)

Your environment

macOS 26.3.1
VSCode 1.113.0
Quarto 1.130.0

[memeplex]

Perhaps the rendering model for notebooks is different, maybe they are rendered cell by cell while working on them, so the option has no useful meaning here.

But the documentation explicitly states:

By default Quarto does not automatically render .qmd or .ipynb files when you save them. This is because rendering might be very time consuming (e.g. it could include long running computations) and it’s good to have the option to save periodically without doing a full render.

https://quarto.org/docs/tools/vscode/index.html#render-on-save

[juliasilge]

Can you say what you mean here by "preview"? Are you looking at the "Quarto Preview" pane as shown in the docs here?
https://quarto.org/docs/tools/vscode/notebook.html

You may want to read more about the execution model for Jupyter notebooks and Quarto rendering here: https://quarto.org/docs/tools/vscode/notebook.html#cell-execution

[memeplex]

Are you looking at the "Quarto Preview" pane as shown in the docs here?

Yes.

You may want to read more about the execution model for Jupyter notebooks and Quarto rendering here

I know about this but I'm not exactly sure about its implications for rendering on save. As the documentation states "rendering might be very time consuming", but if each cell is rendered to html individually perhaps the output is almost there in the ipynb for previewing and it's a very lightweight final step in the case of notebooks, so it doesn't make a lot of sense to provide an option. In any case, either there is a problem in the documentation or in the behavior.