valeriymalov added a comment.
I've tried to restore old behavior, so: - If I run KWindowConfig::restoreWindowSize from dialog's constructor, it doesn't work on multi-monitor setup very well. windowHandle()→screen() seems to be set to leftmost screen (which isn't even primary in my case; is this a bug?), so restoreWindowSize loads saved size for same display no matter on which display the window is opened. Which makes resizing the dialog on any other screen has no effect on the next time it's opened. - If I run KWindowConfig::restoreWindowSize in a timer (like it used to be), it just messes up window positioning because the window is resized after it's been centered by KWin. Probably would mess up KWin rules too. Patch to demonstrate the issue: F5800781: restore_size.patch <https://phabricator.kde.org/F5800781> REPOSITORY R120 Plasma Workspace REVISION DETAIL https://phabricator.kde.org/D3484 To: valeriymalov, #plasma_workspaces, aacid, mart Cc: cfeck, davidedmundson, sebas, aacid, graesslin, plasma-devel, ragreen, Pitel, ZrenBot, lesliezhai, ali-mohamed, jensreuterberg, abetts, apol, mart