1, linux is truly a pain in the ass. On macOS, 3 hours = 5 years worth of learning linux keybinding howto.
2, on linux, i thought, if u r hardcore programer, you'd be able to do far more in keybinding than Mac or windows. Not true at all.
3, i learned the hard way. On linux, there are 10 ways to do it. And the ways are among political factions of desktops X11 xorg ubuntu etc.
500 char limit. see:
Xah keyboard Blog
http://xahlee.info/kbd/keyboard_blog.html