Focus windows only if pointer crosses window border

Submitted by IL'dar Akhmtgaleev

Assigned to Olivier Fourdan @olivier

Link to original bug (#13296)

Description

Currently follow focus not very comfortable for me because of mouse under cursor steals focus when I switch current workspace with keyboard shortcut or when I toggling "Raise or lower window" shortcut. With click to fucus all works as expected but not with follow focus.

How to reproduce:

1. open two non overlapping windows on first workspace
2. activate first window
3. switch to second workspace
4. open third window
5. move mouse pointer in place where second window on first workspace located
6. switch to first workspace expectation: first window still active on first workspace result with follow focus: second window becomes activated result with click to focus: as expected

This behavior makes not possible fast switch between two windows on different desktops. Especially it is annoying on multi-monitor setup where this two windows located on different screens.

As solution windows should be focused only after pointer crosses window's border outside-in.

Version: 4.12.0