hx-trigger="mousedown[button===0]" does not work while "mousebutton[button===1]" does

**Context**
I am working with a password field which also has a button to display the password in cleartext. When I press the button the `blur` event of the input fires and replaces the entire inputfield including the button, so that the `click` event is never fired. It works with a `mousedown` event, however it fires on all mousebuttons not only the primary button.

**Problem**
I wanted to use event filters to check if the primary button had been pressed (`hx-trigger="mousedown[button===0]"`). While it works for secondary (`button===2`) and middle (`button===1`) mouse buttons, it does not seem to work for the primary mouse button. I tested on OSX with Chrome, Firefox, and Safari.

Is `0` handled differently in the event filter mechanism? Do I have to apply the expression differently?

Here is an HTMX **v2.0.6** example to demonstrate:

`index.html`
```

document.addEventListener('mousedown', (e) => {
console.log('Button: ' + e.button + ' is zero ' + (e.button === 0));
console.log('Button: ' + e.button + ' is one ' + (e.button === 1));
console.log('Button: ' + e.button + ' is two ' + (e.button === 2));
console.log('----------');
});

Primary Button

Secondary Button

Middle Button

```

`content.html`
```

content