Like this:

xnview show only solid color on the background.
thank you)
Moderators: helmut, XnTriq, xnview
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CheckerColor1=Colour code
CheckerColor2=Colour code
These two entries allow to change the colours of the chequered pattern items when it's set to represent the transparency.
One can indeed set the two entries as the same value to get a plain background, it's useful sometimes…