I was wondering if WebGL is considered stable enough to be enabled by default. It makes some PDFs render much faster and it has been off by default for a while now, so we have had quite some time to test it.

If we decide to enable WebGL by default, we should not forget to update https://github.com/mozilla/pdf.js/blob/master/extensions/chromium/preferences_schema.json#L39 as well.

/cc @yurydelendik 
/cc @Snuffleupagus (because IIRC you were testing WebGL too)

const x0 = bbox[0],
        y0 = bbox[1],
        x1 = bbox[2],
        y1 = bbox[3];
      
      const matrixScale = Util.singularValueDecompose2dScale(this.matrix);
      const curMatrixScale = Util.singularValueDecompose2dScale(
        this.baseTransform
      );
      const combinedScale = [
        matrixScale[0] * curMatrixScale[0],
        matrixScale[1] * curMatrixScale[1],
      ];
      
      
      
      const dimx = this.getSizeAndScale(
        xstep,
        this.ctx.canvas.width,
        combinedScale[0]
      );
      const dimy = this.getSizeAndScale(
        ystep,
        this.ctx.canvas.height,
        combinedScale[1]
      );