The context menu of the desktop (right-click on an empty area) has as last items "Lock screen" and "Exit". From a UX point of view, they are extremely annoying, because users can accidentally click them and lock screen or exit the session (without any further prompting). It would be nice to remove them from there (deprecate them, point users to use the taskbar menu) or add a prompt saying "are you sure?" etc. I'm for deteting them, IMHO they're not that useful.
These items were in fact removed by default a year and a half ago in https://invent.kde.org/plasma/plasma-workspace/-/commit/ecc938a6663ab56a501ab3e5ffa9ed55444af779 I gather your system is older than that, so you'll need to remove them manually. Right-click on desktop > Configure Desktop & Wallpaper > Mouse Actions > Click the "configure" button next to "Standard menu" > remove whatever yo want from there. If your system is not older than that, then your distro manually re-added these items, so you'll need to bring the matter up with them.
Thanks Nate for the reply, didn't know I could add/remove them. Maybe it's me but I guess that setting is not easily discoverable by the user
Nah, not just you; it's quite hidden indeed.