Koala not compatible with bootstrap 5 maybe need an update

[doc-souhail]

Error: $color: "var(--bs-primary-rgb)" is not a color for `rgba'
on line 47 of C:/Users/Dumball/Desktop/Aurora_Grove/bootstrap-5.1.3/scss/_functions.scss
from line 11 of C:/Users/Dumball/Desktop/Aurora_Grove/bootstrap-5.1.3/scss/bootstrap.scss
from line 3 of C:/Users/Dumball/Desktop/Aurora_Grove/scss/custom_bootstrap.scss
from line 2 of C:\Users\Dumball\Desktop\Aurora_Grove\scss\main.scss

Hello there i think koala doesn't compile anymore on bootstrap 5