Static route based on interface without specifying gateway IP

[THe_ZiPMaN]

Good evening,
I need to add a static route through an interface without specifying a gateway.

From the command line it is really simple to do it, and it works:

# route add 100.99.99.21 -iface vtnet8

But I couldn't discover a way to configure it through the web interface and I really don't want to cheat creating a scripts (it will be undocumented and will be forgotten until something bad happens )

I looked for a solution in the documentation and in the forum and wasn't able to find anything except a similar question in the French forum in 2018 gone unanswered.

Is it possible to create such a route? Should I create a feature request?
Thanks
Flavio Visentin

[lilsense]

under system routes... you can do the same.