This is a regression from PR #4615. The underscore for the last 2 chars in "NUMERO D’IMMATRICULATION" is too bold.

URL: http://www.ameli.fr/fileadmin/user_upload/formulaires/S3706.pdf
1.1.215: https://i.imgur.com/up8Y33j.png
0.8.990: https://i.imgur.com/UioZcLB.png

fc1e2483b433134a538cce0acd0ccc76e335cf5f is the first bad commit
commit fc1e2483b433134a538cce0acd0ccc76e335cf5f
Author: Jonas Jenwald
Date:   Fri Apr 11 20:19:39 2014 +0200

```
Enforce minimum line widths
```

this.ctx.restore();
      this.ctx.save(); 
      copyCtxState(groupCtx, this.ctx);
      
      this.current.resumeSMaskCtx = groupCtx;
      
      
      const deltaTransform = Util.transform(
        this.current.activeSMask.startTransformInverse,
        groupCtx.mozCurrentTransform
      );
      this.ctx.transform.apply(this.ctx, deltaTransform);
      
      groupCtx.save();
      groupCtx.setTransform(1, 0, 0, 1, 0, 0);
      groupCtx.clearRect(0, 0, groupCtx.canvas.width, groupCtx.canvas.height);
      groupCtx.restore();
    },
    resumeSMaskGroup: function CanvasGraphics_resumeSMaskGroup() {
      
      
      
      const groupCtx = this.current.resumeSMaskCtx;
      const currentCtx = this.ctx;
      this.ctx = groupCtx;
      this.groupStack.push(currentCtx);
      this.groupLevel++;
    },
    endSMaskGroup: function CanvasGraphics_endSMaskGroup() {
      const groupCtx = this.ctx;