Summary:
From Wayland documentation:
"When a seat's focus enters a surface, the pointer image is undefined and
a client should respond to this event by setting an appropriate pointer
image with the set_cursor request."
KWin's interpretation so far for the undefined pointer image was to
remove the pointer image when entering a surface waiting for the client
to set a cursor image. This can result in a short flicker as there might
be a frame without a cursor image.
This patch changes the behavior by keeping the previous image till the
application set a new one. This brings some advantages:
* if the application is not responding a cursor is still shown
* if the same cursor is used as in the previous window we don't have a
flicker
CCBUG: 393639
Test Plan: I cannot see the flicker, so only tested with the adjusted tests
Reviewers: #kwin, #plasma
Subscribers: kwin
Tags: #kwin
Differential Revision: https://phabricator.kde.org/D12631
e3250460cc