I've switched to Linux only recently, and am very sad that I had to abandon WinCompose. For those who don't know, it is a taskbar application which allows you to toggle "compose-mode" with your R-Alt key and then combine multiple keystrokes to create special characters in an intuitive way. For example, Alt -> U -> "-" becomes Ū. Is there an alternative to this for Linux? I'm on Zorin OS 17.1 Core, specifically. To clarify, I'm not looking for a symbol table add-on. I'm looking for something that I can utilise with only my keyboard.
Technically, it's inherited from older, non-x86 systems that had a dedicated 'Compose' key on the keyboard. Here's a picture of a Sun Microsystems UK-layout keyboard; take a look at the bottom right of the main section: Link to a wiki hosting the image
(These keyboards also had the Sun (looks like a diamond) key well before Microsoft decided they'd like a Windows key on every keyboard. But then lots of other non-Microsoft computers did that. Apples, Commodores, etc.)
Note that the tiny circle on the key is a light which comes on when the key is engaged and goes off when the composition is complete. The Caps-, Num- and Scroll Lock keys also have built-in lights. For that reason, some people will use Scroll Lock on PC keyboards, especially if the Compose-emulation is able to toggle the Scroll Lock light in the same way.
(Even though I used similar keyboards many, many years ago, I'm not actually sure if the key has the light in it or whether the light is under the key and the circle is merely a window, but that's not really important right now.)
Yes this exists on Linux too, it's called the compose key. It's usually not assigned by default, look in the keyboard settings. I use the Pause key for it.
It works a bit different from WinCompose, you press the key you assigned then two other keys that you want to combine. So instead of using RAlt with the keys you'd press Pause and then each key, one at a time. So Pause then U then " and you'd get Ü.
I'm not sure if the combinations are identical but it would make sense if they were.
Dead keys are another method of doing diacritics but what OP is describing is the compose key, which is independent of layout and can do more symbols not just diacritics.
Check your keyboard layout. Perhaps add whatever language keyboard you are looking to use the characters from? In my case, I couldn't find a Welsh keyboard but the UK English keyboard has keystrokes for characters like ŵ. That could potentially be an option.