tiling window managers not following cursor focus

[kkk9]

I initially noticed this with i3wm, which I often used on Arch Linux, and decided to use on Gentoo as well.
While on Arch, when hovering the cursor on a given window or frame/container, the focus focuses the position of the cursor.
On Gentoo with the same configuration, however, this does not happen. Taking in consideration that the i3 configuration is the same (in all fairness, it's actually the default one), I don't really know where the difference is.
Sometimes (quite often) the cursor focus remains stuck, allowing only to type while unable to point.
Do you have any clue of what could be the cause?

I hope this makes any sense,


--- EDIT: despite having the same configuration, i3wm behaves differently in Arch from what it does on Gentoo. I solved the issue by adding