GUI: mouse wheel scrolls wrong window

[unclechu]

I set maps for mouse wheel as in the example from README:

noremap <silent> <ScrollWheelDown> :call comfortable_motion#flick(40)<CR>
noremap <silent> <ScrollWheelUp>   :call comfortable_motion#flick(-40)<CR>

GUI: neovim-gtk
Neovim version: v0.3.0-1233-gde7a0bdc3
When I scrolling right window by placing mouse cursor on it, "comfortable" scrolling happens in left window. See this short screencast which demonstrates it: https://youtu.be/SlHV9JrkEq8

[nkakouros]

This happens on the terminal as well.