<details>
  <summary><code>FzfxKeyMaps</code> (Search vim key mappings)</summary>
  <small>
    <ol>
      <li>Press <code>enter</code> to execute key mapping.</li>
      <li>
        <b>Select keys</b> is disabled (since it is not allowed to execute
        multiple key mappings).
      </li>
      <li>
        <b>Normal mode</b> variant is named with <code>n_mode_</code> prefix.
        <b>Insert mode</b> variant is named with <code>i_mode_</code> prefix.
        <b>Visual/select mode</b> variant is named