A few days ago my display in Kubuntu 18.04 suddenly was magnified as if, from that time onward, a virtual display has been kept in memory which is perhaps twice as large vertically and horizontally as my physical display. The virtual display thus contains a magnified version of what I want on my physical display. My physical display then presents only perhaps one quarter of the virtual magnified display, depending on where my mouse pointer is. For instance when I move my mouse pointer to the left hand top corner of my physical display the left hand top ~1/4 section of the virtual (magnified) display will be displayed on my physical display. I can still use my laptop this way but, as you probably can imagine, it is awkward. I am writing the posting you are reading on this laptop. I have used Kubuntu for many years. Since my last installation of 18.04, perhaps about 6 months ago, it has been running acceptably on my old System_76 Bonobo Extreme laptop. It would seem that pressing some combination of keys, or something in settings, should get me out of this mode. Rebooting my laptop does not solve the problem. I have worked for hours on trying to solve this problem without any luck, or find mention of any other user of Kubuntu (or Ubuntu) having the same problem. Does this kubuntu related question belong here or in a KDE forum?
The question in the title belongs to Meta Ask Ubuntu
The question in the title is about Ask Ubuntu. Therefore it belongs to Meta Ask Ubuntu.
The question in the Body belongs to Ask Ubuntu
The question in the body is about Kubuntu 18.04. Kubuntu is an official flavor of Ubuntu and the version 18.04 is one of the currently supported versions. Thus, the question in the body belong to Ask Ubuntu.
Note, once a version of Ubuntu (and its official flavors, such as Kubuntu) reaches its end of life, questions about such unsupported versions are not valid in Ask Ubuntu.
Hope this helps