Shows a cursor on the waveform.
let wavesurfer = WaveSurfer.create({
container: document.querySelector('#waveform'),
plugins: [
WaveSurfer.cursor.create({
showTime: true,
opacity: 1,
customShowTimeStyle: {
'background-color': '#000',
color: '#fff',
padding: '2px',
'font-size': '10px'
}
})
]
});