I just erased my Whonix 13 templates/VMs in Qubes 4, and replaced with Whonix 14 as per the upgrade docs.
Post-install I ran
sudo qubesctl state.sls qvm.whonix-ws-dvm, as I use Whonix DispVMs.
This created the whonix-ws-14-dvm as expected.
However, when I launch a Whonix DispVM’s TorBrowser, I get an error ‘Do not run Tor Browser in Qubes DVM Template!’
This is a surprise because I’m not intending on running it in a template - I’m launching a new DispVM from the Qubes ‘start’ menu (Disposable: whonix-ws-14-dvm -> Tor Browser), which previously always created a new DispVM.
So in fact, it seems that starting a DispVM is not actually starting a DispVM, it’s instead booting the whonix-ws-14-dvm TemplateBasedVM. I verified by checking in the Qube Manager that it’s actually booting the templatebased VM instead of starting a dispXXXX.