code: function savePoint() {
    if (input.value.trim().length > 0) {
      let clientX = parseInt(input.style.left, 10);
      let clientY = parseInt(input.style.top, 10);
      let content = input.value.trim();
      let svg = findSVGAtPoint(clientX, clientY);
      if (!svg) {
        return;
      }
  
      let rect = svg.getBoundingClientRect();
      let { documentId, pageNumber } = getMetadata(svg);
      let annotation = Object.assign({
          type: 'point'
        }, scaleDown(svg, {
          x: clientX - rect.left,
          y: clientY - rect.top
        })
      );
  
      PDFJSAnnotate.getStoreAdapter().addAnnotation(documentId, pageNumber, annotation)
        .then((annotation) => {
          PDFJSAnnotate.getStoreAdapter().addComment(
            documentId,
            annotation.uuid,
            content
          );
  
          appendChild(svg, annotation);
        });
    }
  
    closeInput();
  }
docs: Save a new point annotation from input