Define default session properties for new sessions

I note that if I change a session property on a particular PC, the next time that PC loads up a new session, it will remember the session properties and use them again next time.

For example, on a new PC, the session will open in light mode. I can change it to dark mode, and the next time a session is opened on that PC, it will open in dark mode.

How can I make dark mode the default for all new sessions?

Just to clarify so I don't assume.

Are you talking about the Designer, Vision, Perspective?

You can put an expression binding on session.props.theme that just returns dark to ensure it's always dark by default.

That would force it to be dark all the time though, correct?

The theme was just one example - there are about 5-10 session properties that I set up with each new device, but it'd be much easier if I could just set something at the gateway level that says "these are the defaults that each new device uses as a starting point". If on one device the users want a different option, no problem, they can select that - but it just means that anyone who spins up a session on any device will get a familiar environment to start, and if they want to change it, they can.

An expression binding with a static value in it will only execute once, on startup.

I would probably contact support to explain what's going on in more detail, though; I don't think this is expected behavior.