ParticleEmitterManager using wrong texture frame

I have this spritesheet, a white point and a black point:

effects

(The white point is not visible on the white background)

I load it like this:

this.load.spritesheet('effects', 'effects.png', { frameWidth: 8, frameHeight: 8 });

And then I use it for particles:

let particles = getScene().add.particles('effects', 1);

I want to select the black point. The black point is second in the image. However, this code does select the white point.

If I change the 1 for a 2, I get an error in the console:

Texture.frame missing: 2

Makes sense. The emitted particles are solid white now (not my white point). If I change the frame to 0, there is no error but I get the same solid white.

What is going on here?

How can I make particles use the black point?

I’ve just tried to load them individually:

this.load.image('white', 'white.png');
this.load.image('black', 'black.png');

Then, when I try to use them for particles:

let particles = getScene().add.particles('white');

in case of white I get solid white particles (not my smoothed white point); in case of black I don’t see any particles at all.

Something is very weird is going on here…