CSS Color Level 4

[chiefss]

This style throw exception com.inet.lib.less.LessException: Not supported Oprator ' ' for Expression '255 122 127 / .2'
background: rgb(255 122 127 / .2);

The Level 4 specification also allows for space-separated in addition to comma-separated values.

[Horcrux7]

If I look into documentation of lesscss I can't see that this is supported: https://lesscss.org/functions/#color-definition-rgb

Can you point me to the position where this is documented.

[chiefss]

For example rgb():

CSS Colors Level 4 made some changes to rgb(). In browsers that support the standard rgba() is an alias for rgb(), they accept the same parameters and behave the same way.
The Level 4 specification also allows for space-separated in addition to comma-separated values.

https://www.w3.org/TR/css-color-4/
https://developer.mozilla.org/en-US/docs/Web/CSS/color_value/rgb

Alsa with rgb(), rgba(), hsl(), hsla(), hwb(), lab(), lch(), oklab(), oklch(), color()

[Horcrux7]

This is CSS syntax and not lesscss syntax. This are different things. If you want bypass an expression then you can escape it with:

background: e( "rgb(255 122 127 / .2)" );
or
background: ~"rgb(255 122 127 / .2)";