It’s a checkbox in the installer, easy to miss. Has defaulted to off for a very long time now, basically ever since SSDs have been commonplace.

The default depends on your storage. It has defaulted to not load on startup for me any time I’ve installed it to an SSD.

I’d argue that Li should be red and Hg should be yellow.

Elemental mercury in liquid form is fairly safe. It needs to get into your blood in order to be a problem, and even if some does stick to your tongue and get swallowed the digestive absorption is extremely low.