           <table>
             <thead>
               <tr>
-                {<th>{column}</th> for column in MANIFEST_COLUMNS}
+                {for column in MANIFEST_COLUMNS
+                  <th key={column}>{column}</th>}
                 <th></th>
               </tr>
             </thead>

      <tr key={filenames.join()}>
        <td>
          {for filename, i in filenames
            <div>
              {filename}
              {unless files[i]?
                <span className="form-help error" title="Missing image">&nbsp;<i className="fa fa-exclamation-circle"></i></span>}

          <p>These images will be uploaded during after last step of this process, which could take a long time depending on how many you select. Make sure you’ve got a steady internet connection. You’ll have an opportunity to review and refine your selection here before continuing.</p>

          {for manifestFilename of wizardData.manifests
            <span key={manifestFilename}>
              {manifestFilename}
              <button onClick={@removeManifest.bind this, manifestFilename}>&times;</button>
              &emsp;
