Hello LookingGlass users!
As of commit 4f8fa6e it’s now possible to have clipboard support in looking glass!
However, you may have noticed that your mouse is no longer moving properly after installing spice guest agent tools in your guest.
The problem lies with the QXL device being also present in your virtual machine (because libvirt adds it by default if you are using spice)
To fix this, we have to explicitly tell libvirt not to add a QXL device when starting the virtual machine, as disabling the QXL driver does not work reliably and may re-enable itself after several reboots.
All you have to do to remove the QXL device is replace your current video tag with this:
<video>
<model type='none'/>
</video>
It’s located under: domain/devices
I hope this saves you some trouble, it took several days to figure this out myself!