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Well if you use orb.detect without the noArray1 argument you'll get the keypoints for the whole image, the following code should print all your keypoints on your image.

let orig = cv.imread(canvasOutput1);
var orb = new cv.ORB(10000);
let des = new cv.Mat();
let img3 = new cv.Mat();
var kp1 = new cv.KeyPointVector();
// find the keypoints with ORB
orb.detect(orig, kp1);
// compute the descriptors with ORB
var das=new cv.Mat();   
orb.compute(orig, kp1, das);
cv.drawKeypoints(rsrc2, kp3, img3, [0, 255, 0, 255]);
cv.imshow('canvasID', img3);

According to the official documentation the noArray1 argument should have the information about where thee algorithm should look for the keypoints, but I haven't use that.

Well you could try using kp1.get(0) to check the contents of the first keypoint you have.

Also if you use orb.detect without the noArray1 argument you'll get the keypoints for the whole image, the following code should print all your keypoints on your image.

let orig = cv.imread(canvasOutput1);
var orb = new cv.ORB(10000);
let des = new cv.Mat();
let img3 = new cv.Mat();
var kp1 = new cv.KeyPointVector();
// find the keypoints with ORB
orb.detect(orig, kp1);
// compute the descriptors with ORB
var das=new cv.Mat();   
orb.compute(orig, kp1, das);
cv.drawKeypoints(rsrc2, kp3, img3, [0, 255, 0, 255]);
cv.imshow('canvasID', img3);

According to the official documentation the noArray1 argument should Check if that work for you, if not maybe you could have the information about where thee algorithm should look for the keypoints, but I haven't use that.some issue with your opencv.js file, what version are you using?