Firefox and Chrome have been using hardware acceleration for Skia for ages. Even if you have HW acceleration shut off, Chrome is typically using SwiftShader to

Firefox and Chrome have been using hardware acceleration for Skia for ages. Even if you have HW acceleration shut off, Chrome is typically using SwiftShader to rasterize which basically emulates a GPU instead of doing traditional CPU rasterization. If you switch off hw accel in Chrome and Firefox your canvas performance will tank.