Or try Work Environment > User Preference Schemes > On-Screen Options > Display Editing Plane during editing operations only.
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David
David Maudlin / Architect www.davidmaudlin.com Digital Architecture AC27 USA • iMac 27" 4.0GHz Quad-core i7 OSX11 | 24 gb ram • MacBook Pro M3 Pro | 36 gb ram OSX14
If you want to just tone it down a bit, whilst in the 3D window you can go to View>Grid & Editing Plane Options> Grids & Background. From there you can adjust the color and opacity of the background, which is what the editing plane uses.