localStorage inaccessible within jupyter html browser

[ClaytonAstrom]

Hey!

Just a quick note -

furo/src/furo/theme/furo/base.html

Line 86 in c790c6d

document.body.dataset.theme = localStorage.getItem("theme") || "auto";

will throw when pages are opened in jupyterlab's html viewer - jupyterlab/jupyterlab#5855 (or similar iframe environments)

[pradyunsg]

Hmm... this theme's dark mode / light mode mechanisms have a baked-in assumption that it's being used in a regular non-sandboxed browser environment.