Bug to be fixed: Helium scss errors

I just upgraded Helium theme on two websites from 5.5.23 to 5.5.25 and I had to fix
in g5_helium/scss/helium/sections/_offcanvas.scss
on row 35
left: $offcanvas-width - 3rem;

I edited this way and now they work
left: calc($offcanvas-width - 3rem);

Please fix these bugs