kitty does not render cursor correctly when fg&bg are set to reverse on the text under the cursor

[zhou13]

To Reproduce
Steps to reproduce the behavior:

1. make sure cursor none is in kitty's config
2. open vim /etc/profile
3. type :syntax on and press enter
4. type :colorscheme torte and press enter
5. type :set hls and press enter
6. type /if and press enter
7. you will find your cursor missing. This is probably because if is highlighted with reverse in vim, which conflicts with cursor none

Expected: See iTerm2 result, where i is correctly highlighted. Note that my iTerm2 is also configured so that fg&bg is swapped on cursor.