Can I get close buttons to plasma widgets?

I updated recently from kubuntu 14.04 to 18.04 and got new plasma 5.12.6. However, the widgets (like network manager, volume, battery, calendar etc) are all missing close buttons (crosses on the right top corner). I can close them by clicking the right icon on the toolbar again but it is slower and more difficult (first you need to know which icon to click, if it was opened accidentally, and second you need better eye-hand coordination since the toolbar icons are so small and close to each other). Instead of close buttons, there are useless pin buttons (which I always click accidentally, when searching for close).

I am also remembering that in old plasma, it was possible to close widget windows by clicking anywhere the toolbar.

Is this a new feature of plasma widgets? Is it possible to get the old close buttons back? Or the behaviour to close widgets by clicking the toolbar anywhere?

Edit: Below a screenshot showing the task bar and one widget open.