in js/bootstrap.bundle.js [5305:5343]
_getPopperConfig(attachment) {
const defaultBsPopperConfig = {
placement: attachment,
modifiers: [{
name: 'flip',
options: {
fallbackPlacements: this._config.fallbackPlacements
}
}, {
name: 'offset',
options: {
offset: this._getOffset()
}
}, {
name: 'preventOverflow',
options: {
boundary: this._config.boundary
}
}, {
name: 'arrow',
options: {
element: `.${this.constructor.NAME}-arrow`
}
}, {
name: 'preSetPlacement',
enabled: true,
phase: 'beforeMain',
fn: data => {
// Pre-set Popper's placement attribute in order to read the arrow sizes properly.
// Otherwise, Popper mixes up the width and height dimensions since the initial arrow style is for top placement
this._getTipElement().setAttribute('data-popper-placement', data.state.placement);
}
}]
};
return {
...defaultBsPopperConfig,
...execute(this._config.popperConfig, [defaultBsPopperConfig])
};
}