url_tracker_tool/node_modules/react-dropzone/examples/maxFiles

By providing maxFiles prop you can limit how many files the dropzone accepts.

Note that this prop is enabled when the multiple prop is enabled. The default value for this prop is 0, which means there's no limitation to how many files are accepted.

import React from 'react';
import {useDropzone} from 'react-dropzone';

function AcceptMaxFiles(props) {
  const {
    acceptedFiles,
    fileRejections,
    getRootProps,
    getInputProps
  } = useDropzone({    
    maxFiles:2
  });

  const acceptedFileItems = acceptedFiles.map(file => (
    <li key={file.path}>
      {file.path} - {file.size} bytes
    </li>
  ));

  const fileRejectionItems = fileRejections.map(({ file, errors  }) => { 
   return (
     <li key={file.path}>
          {file.path} - {file.size} bytes
          <ul>
            {errors.map(e => <li key={e.code}>{e.message}</li>)}
         </ul>

     </li>
   ) 
  });
  

  return (
    <section className="container">
      <div {...getRootProps({ className: 'dropzone' })}>
        <input {...getInputProps()} />
        <p>Drag 'n' drop some files here, or click to select files</p>
        <em>(2 files are the maximum number of files you can drop here)</em>
      </div>
      <aside>
        <h4>Accepted files</h4>
        <ul>{acceptedFileItems}</ul>
        <h4>Rejected files</h4>
        <ul>{fileRejectionItems}</ul>
      </aside>
    </section>
  );
}

<AcceptMaxFiles />