OffscreenCanvas not supported on old browsers

## Description

Users on old browser versions (~2022) can run into a crash because OffscreenCanvas is not supported. See https://caniuse.com/offscreencanvas.

This is also a known bug in TFE.

Can we fix this by adding a polyfill?

## Expected Behavior

CFE should not crash, or should instead show a warning about outdated browsers.

## Reproduction

Try opening http://staging.cfe.allencell.org Firefox version 103.

## Environment

_Any additional information about your environment. E.g. OS version, python version, browser etc._