[nuclear_eclipse]

You can do very similar things on macOS. `Option+E, A` generates á, `Option-U, U` yields ü, and so forth. There are tons of alternate characters available like this using the Option keys, generally covering the most used glyphs I've needed. Beyond that, the Rocket app is fantastic for finding and inserting emojis and more complicated emoticons by human-friendly name.

[boogies]

That’s not the same, that’s basically just AltGr. In X you can do ‘Compose, o, o’ → °, ‘Compose, C, o’ → ©’, ‘Compose, s, o’ → §, ‘Compose p o o’ → «a character HN doesn’t allow (U1F4A9)» and ~6000¹ other combinations. X also has a “mac” layout variant I’d like to hear a macOS user’s opinion of (haven’t ever wanted to use it myself).

[1]: ± some depending on if you count multiple ways of creating the same character, etc. Eg. ‘≠’ can be made by combining / and = in either order. Also ‘Compose, number, s’ for footnotes, ‘Compose, +, -’ → ±, ‘Compose , <, '’ → “‘”, ‘Compose, -, >’ → “→”, ‘Compose, =, >” → “⇒” are nice. And υɳⅰеηⅽоⅾе.