Is there a way to "lock" a layer so it's not selectable?

[Hank (Hank Morgan)]

I’ve got an image on screen and I’m trying to trace a complex outline so I can cut some gaskets.
When node editing the outline it’s too easy to miss by a bit and end up selecting the background photo by mistake.

Is there a way to lock a layer so it’s still fully visible but can’t be selected or messed with?

[Hank (Hank Morgan)]

Why yes, it most certainly is!
Thank you very much!

[Rick (Technical Evangelist)]

And from the context-menu as well…

[Hank (Hank Morgan)]

Thanks Rick!