Hi Arald,
Just place your resources in the theme\img or theme\resources folder and adjust just Sass file accordingly to not get the images from the Sass folders, but ‘higher’ up.
Like so:
.brand-logo {
background-image: url(../../../img/logo.svg); // Replaced (../../sass/custom/_companyspecific/img/logo.svg)
}
From the release notes of 8.14: