Not the ones in this implementation though.

If do a Ctrl-+, they do get bigger with no jaggies. So that is some level of scaling.

OTOH, I don't know that there is any way to take these icons and draw them at a larger size without creating new CSS.

Oh, it's because I have enabled "Text-only zoom" in Firefox. I expected the icons to be sized in "ems" so that their size would be relative to their element's font size.