Reproduce:

• Create a boot app.
• launch from boot dash
• open launccnfig editor
• add some invalid text to props editor. For example:

something.unknown=888

There should be 'unknown property warning. And actually there is but it isn't marked in the editor (no squigly lines to indicate the problem). When I hover over the 'bad' property name however there's a popup showing the warning.

So I think the warnings are still there but the editor isn't properly rendering these markers in the text.