Are you sure it's supposed to be "Mandela effect"?

Yes; it is named for the mistaken belief that Mandela died in prison during the 80s.

Nope. Ironically that’s something people misremember about the origin of the Mandala effect, which existed long before Nelson Mandela died.

But he did?

Or didn't he?

Whoosh :)

Like aluminum and flavor. My spellchecker does not agree even if I write those words correctly.

You have your spellchecker set wrong: you need to set it to US English, not UK English.

It defaults to US. That is why it doesn't like correctly spelled colours and flavours of aluminium.