And I see the same error with

squeak -headless -- -evaluate '[Preferences setDemoFonts] 
valueSupplyingAnswer: true'

Cheers,
   Tony


On 5/25/22 17:09, Tony Garnock-Jones wrote:
> Hello all,
> 
> With the latest 6.0 beta image and a from-git `Cog` branch VM freshly 
> compiled on Debian x86_64, I see the following:
> 
> squeak -- -evaluate '[Preferences setDemoFonts] valueSupplyingAnswer: true'
> 
> --> correctly evaluates, answers `Preferences`
> 
> squeak -vm-display-null -- -evaluate '[Preferences setDemoFonts] 
> valueSupplyingAnswer: true'
> 
> --> fails, with `Error: primitiveWindow:width:height: failed`
> 
> This didn't used to happen! Has something changed wrt vm-display-null?
> 
> Cheers,
>    Tony
>