I use the laptop screen + external monitor (DP), which powers off after a while idle. If its in the lock screen, being shown at the laptop (which is my secondary screen), and I turn on the external one, it will move the password dialog to the external one but it clearly happens in (paused) stages and only allows me to type the password after like, 15 seconds or so. Seems that typing a tab might help, but I'm not sure if it's not just a coincidence or not. It works, it just has this annoying delay.
The password dialog in Plasma 5 should show on all screens all the time, so I understand it as that you turn on the external monitor and turn off laptop monitor. This will result in the screen buffer being shown on the monitor, but the *actual* window of the screen locker is not yet there, so you are not really clicking on it. This is due to KScreen and Qt taking lots of time to figure things out and reshuffle the screens. The switch should be much much faster (ideally less than a second) with Qt 5.5.
Yeah, I was just going to update this BZ. I disabled the lockscreen for now and I noticed that the same slowdown still happens. The external one, which has a bigger resolution than the laptop one, exhibits a tiled version of the laptop screen for quite some seconds before redrawing it correctly. So now I think this is not lockscreen fault, at least not entirely. I did a video of the issue, but I can't transfer it from my phone. Seems kdeconnect is corrupting the file and via USB is also not working. I'll post a link when I get it. Feel free to redirect this BZ to wherever you think it's more suitable. Thanks.
That's the same problem - switching screens takes some time + it takes some time for plasmashell and kwin to react to notice the change and react correctly. As I said before, this will be fixed with Qt 5.5, I'll see if I can backport the patch to Qt 5.4.
Cool, thanks! Then I'll not bother on getting that video online..
update: our attempts at backporting this to 5.4 ended up being impractical, so we're deferring to just waiting for Qt-5.5 to land, and will update at first opportunity.
Any idea if we will get that before F22 is out? Because this bug is really annoying.
Not in time for F22 initial release, but as an update soon after (hopefully). Qt 5.5 is currently targetted for May 26, see: https://wiki.qt.io/Qt-5.5-release
Okay, thank you.