Yes, but I assumed that disabling the TV would set the monitor as the primary desktop and added the taskbar to it, but it didn't. Now I may have done something wrong, but I was just reporting my experience.

It remembers the screens to try to keep your settings if you disconnect and reconnect external screens, but in this case that was not very helpful

I always want the taskbar on every screen personally. I think that'd be a friendlier default, but since it's KDE it's at least not too hard to change, and everything is configurable down to fine details

If unplugging the display cable works though. It's most likely the TV pretending to be still on.

I have a LG TV C1 that behaves like that. While my computer monitors do not have this issue.

The TV even has a dual personality. It doesn't appear to report the same informations via EBID when powered off vs powered on.

I also have a MS Windows 10 connected to this same TV, and if I make the mistake of powering up or wake from sleep Windows before turning on the TV, then the NVIDIA GPU setup some broken resolution. And only a reboot fixes it.

So my guess is it's the TV presenting itself with different EBID when off vs powered on. And also somehow presenting itself as active on the HDMI line no matter if off or on. Changing the TV inputs also doesn't tell KDE that the display was turned off.

I haven't debugged any of it. These are just my observations.

It should do that. If I unplug my external monitor the panel moves to the laptop, and it even turns it on if its been disabled.

Then it's likely that plasma just crashed :')