[@material/react-select] outlined Select's border is lighter than TextField's

[kino90]

Hello.
I'm building a form with all fields (@material/react-text-field) set as "outline" style.
In this form I also have a Select component, but the color of the outline is slightly different.

<Select>'s border-color is rgba(0, 0, 0, 0.24);, while <TextField>'s is rgba(0, 0, 0, 0.38);