On Unity-based Ubuntu, I could bring up the Character Map quickly from the Text Entry menu:
How might I restore similar functionality under Ubuntu Gnome? I use a lot of Unicode characters, and it wouldn't be practical to set up XCompose sequences for all of them.
31 Answer
I've just upgraded Ubuntu from 16 to 18, and had the same issue. After installing gucharmap that functionality was restored. (I find the new character map a cute complement, but not a replacement.)
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