When I use renderFunction the wave is redrawn twice

[baranowskyi]

I encountered the following issue: when I use a custom function for drawing the waveform, it gets called twice during WaveSurfer initialization. What could this be related to?

I also tested this with code from the documentation, and the rendering happens twice. I also noticed that the canvas is drawn with one size and only then takes the size passed in the properties.
<canvas width="1407" height="175" style="width: 804px; height: 100px; left: 0px;"></canvas>
Could this be the reason?