I am porting some code from Jupyter Notebooks to Quarto documents within VSCode. I have a few scatter plots with millions of points on them, and both the browser and VSCode crash/hang trying to render these as SVG. I added fmt=:png in the Jupyter notebook so that they would be displayed as raster, which solved the problem in Jupyter, but this does not seem to have any effect in VSCode. Looking at the developer tools I see the plot is still rendered as SVG:
I created a MWE that loads a 10 million row dataset and makes a scatterplot. Rendering as a Quarto document works fine and embeds a PNG, but running in VSCode produces an SVG.