[duskwuff]

Whoops, I totally didn't notice that was missing from the list.

That being said, while Apple hasn't explicitly said they plan to remove Flash from desktop Safari, they've implicitly signalled it -- they've already got features in place which make it often only load on demand.

[caryhartline]

There's not much to remove. You install Flash on macOS separately and Safari will load that in as a plugin. It seems obvious that Safari will remove that plugin functionality on or before 2020.