SUMMARY a) The default and only behavior was to show an auto-hide panel as long as any window wants attention - effectively interrupting the workflow and forcing the user to switch to that window. b) With bug 394119 there will be an option, to suppress "show-on-notification" completely. I like to discuss an middle-ground ideas between a) obtrusive and b) silenced notification: 1. Dismiss on timer - notification auto-revokes after a few seconds 2. Dismiss by mouse-over - specifically the mouse-exit will take precedence on hiding the panel irrespective of any notification status. See also https://phabricator.kde.org/D12916#500345 3. Suppress panel unhide like b) but instead show notification bubble with window-icon + title and a click will bring the window to front Questions: I. Will notifications be lost, that the user might want to review later? Then the autohide should be decoupled from notification present, so that on next mouse-over the window in the taskmanager should still display a highlight to signal, it still wants attention. II. Notification bubbles already offer a timer, that stops on mouse-over - same mechanism could be a applied to the panel. Only the panel may not show an X to "close" because we will not want to "terminate" the panel. Instead the icon could be an arrow in direction to the screen-edge the panel is attached to, to signify the go-away notion.
(In reply to Holger from comment #0) > 2. Dismiss by mouse-over - specifically the mouse-exit will take precedence > on hiding the panel irrespective of any notification status. This is precisely how it used to work in KDE3-4 as far as I recall, so the absence of this feature in KDE5/Plasma can be considered a regression. To be specific, it would re-show if a window _changed_ its "wants attention" flag to true - so the panel would re-show if a window stopped wanting attention but then wanted it again, I guess making it more like an event than a flag.
This issue is still present in plasma desktop/workspace 5.21.5 fwiw