with fixed and scrollable [duplicate]

Chrome, FF, Edge
the simplest solution is to use th { position: sticky; top: 0; }

/* JUST COMMON TABLE STYLES... */
table { border-collapse: collapse; width: 100%; }
th, td { background: #fff; padding: 8px 16px; }


.tableFixHead {
  overflow: auto;
  height: 100px;
}

.tableFixHead thead th {
  position: sticky;
  top: 0;
}

<div class="tableFixHead">
  <table>
    <thead>
      <tr><th>TH 1</th><th>TH 2</th></tr>
    </thead>
    <tbody>
      <tr><td>A1</td><td>A2</td></tr>
      <tr><td>B1</td><td>B2</td></tr>
      <tr><td>C1</td><td>C2</td></tr>
      <tr><td>D1</td><td>D2</td></tr>
      <tr><td>E1</td><td>E2</td></tr>
    </tbody>
  </table>
</div>

IE11

To sloppily support IE11 (2.5% market share as of 10/2018), a bit jaggy but at least THs are on top – you could add this JavaScript:

function isIE() {
  return navigator.userAgent.indexOf('MSIE') > -1 || navigator.appVersion.indexOf('Trident/') > -1
}


if (isIE()) {

  // Fix table head
  function tableFixHead(ths) {
    var sT = this.scrollTop;
    [].forEach.call(ths, function(th) {
      th.style.transform = "translateY(" + sT + "px)";
    });
  }

  [].forEach.call(document.querySelectorAll(".tableFixHead"), function(el) {
    var ths = el.querySelectorAll("thead th");
    el.addEventListener("scroll", tableFixHead.bind(el, ths));
  });

}

which will (since IE ignores sticky position) use transform translateY to position the TH elements.

PS: the above JS (without the wrapping if statement) works pretty decently for all other evergreen browsers too – in case position: sticky; does not fits your needs…