In my case, the issue was caused by @property being wrapped inside an @layer. Moving the @property declaration to the top level of the stylesheet solved the crash.

Before:

@layer base {
    @property --my-color {
       syntax: "<color>";
       initial-value: #fff;
       inherits: true;
    }
    /* others */
}

After:

@property --my-color {
    syntax: "<color>";
    initial-value: #fff;
    inherits: true;
}
@layer base {
    /* others */
}