I upgraded my Ubuntu recently from 19.04 (Disco) to 19.10 (Eoan Ermine). At some point, I noticed that Shift+Tab stopped working in vim. I use nvim and have Tab configured to move to the next tab and Shift+Tab configured to move to the previous tab. Tab worked, Shift+Tab didn’t. It’s two lines in my .vimrc: nmap <Tab> :tabnext<enter> nmap <S-Tab> :tabprev<enter> Maybe it’s nvim? At first, I suspected it’s a problem with nvim since I upgraded it as well and there is some old article mentioning how to get Shift+Tab to work.