I’m unsure what vscode does to the plot size, if the plot size is > window size. Gadfly.set_default_plot_size definitely works e.g. in Jupyter, or when saving the figure. You might be able to get this suggestion to work in vscode, but I’ve not tested it in vscode (you might have to popdisplay() first, which would move Gadfly’s display to the top of the display stack).
Also see similiar post here.