A lot of widgets in kde plasma desktop have alternative feature when middle-clicked (Example: mute/unmute when midclick volume widget etc). In Pager widget however you can left-click another virtual desktop to move to it or ”show desktop” when clicked on current virtual desktop; There is no alternative feature for a middle-click in this widget. The most obvious one (for me personally) would be to get to ”overview” mode when middle-click, because as I know there is no widgets dedicated to simply show overview and its only key shortcut feature; this feature can be optional and placed alongside with others in widget settings.
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