Glass effect on a stroke

I'm trying to apply a glass effect on a circle stroke but all it does is apply it to the circle itself and not the stroke:

import SwiftUI

let kCarouselCircleSize: CGFloat = 150
let kCarouselOpacity: Double = 0.3
let kCarouselStrokeWidth: CGFloat = 60

struct ContentView: View {
    @State var showing = false
    
    var body: some View {
        VStack(spacing: 60) {
            Text("ultraThinMaterial:")
                .font(.title)
            CarouseCircle(drawProgress: 0.7, isActive: false)
            Text("glassEffect()")
                .font(.title)
            CarouseCircle(useGlassEffect: true, drawProgress: 0.7, isActive: false)
        }
        .background(content: {
            Image(.background2)
        })
        .padding()
    }
}

struct CarouseCircle: View {
    var size: CGFloat = kCarouselCircleSize
    var strokeWidth: CGFloat = kCarouselStrokeWidth
    var useGlassEffect: Bool = false
    
    var drawProgress: CGFloat
    var isActive: Bool
    
    var body: some View {
        if useGlassEffect {
            Circle()
                .trim(from: 0, to: drawProgress)
                .fill(.clear)
                .stroke(.blue, style: StrokeStyle(lineWidth: strokeWidth, lineCap: .round))
                .frame(width: size, height: size)
                .glassEffect()
                .shadow(color: .black.opacity(kCarouselOpacity), radius: isActive ? 4 : 1, x: 0, y: 0)
                .rotationEffect(.degrees(-90)) // Start drawing at button 1's position
        } else {
            Circle()
                .trim(from: 0, to: drawProgress)
                .fill(.clear)
                .stroke(.ultraThinMaterial, style: StrokeStyle(lineWidth: strokeWidth, lineCap: .round))
                .frame(width: size, height: size)
                .shadow(color: .black.opacity(kCarouselOpacity), radius: isActive ? 4 : 1, x: 0, y: 0)
                .rotationEffect(.degrees(-90)) // Start drawing at button 1's position
        }
    }
}

Here's the result:

Is this supported, a bug or something I'm doing wrong?