JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.29.1/moment.min.js"></script>

JavaScript

/**
 * タイムスタンプを整形して返す
 * 
 * @param {string} ssms 秒(ss)とミリ秒(ms)で構成されたタイムスタンプ e.g. "4080.770" (01:08:00.770)
 * @return {string} showTime e.g. "1:8:0.77"
 */
function formatTimestamp(time = 0)
{
  if(time == 0){
    return "0:0:0";
  }

  var ssms = time.split(".");

  var temp_ss = ssms[0];
  var temp_ms = ssms[1] ? ssms[1] : 0;

  var m = moment.utc(temp_ss * 1000);
  var hms = m.format("H:m:s");

  var ms = removeTrailingZeros("." + temp_ms);

  ms = ms ? ms : "";

  var showTime = hms + ms; 

  return showTime;
}

/**
 * 数字文字列の末尾のゼロを除去して返す
 * 
 * [EXAMPLES]
 * 1 -> 1
 * 10 -> 10
 * 100. -> 100
 * 100.0 -> 100
 * 100.1 -> 100.1
 * 100.10 -> 100.1
 * 100.01 -> 100.01
 * 100.010 -> 100.01
 * '1.2304000' -> 1.2304
 * '1,000.000' -> 1,000
 * 
 * @param {string|integer} value 数字文字列
 * @return {string} value 末尾ゼロを除去した数字文字列
 */
function removeTrailingZeros(value)
{
  var value = value.toString()

  //console.log('Starting with:', value, value.indexOf('.'))

  // ドット(ミリ秒)を含まない場合はそのままの値を返す
  if (value.indexOf('.') === -1) {
    return value;
  }

  var cutFrom = value.length - 1;

  // ゼロの削除を末尾からドットの方向へ繰り返す
  do {
    //console.log('Checking:', value[cutFrom], cutFrom)

    if (value[cutFrom] === '0') {
      cutFrom--;
    }
  }
  while (value[cutFrom] === '0');

  // ドットの位置に来たら処理を終了する
  if (value[cutFrom] === '.') {
    cutFrom--;
  }

  return value.substr(0, cutFrom + 1);
}

console.log(formatTimestamp("4080.770"));
console.log(formatTimestamp("3600"));
console.log(formatTimestamp("2045"));
console.log(formatTimestamp("1000.000"));
console.log(formatTimestamp("1000.001"));
console.log(formatTimestamp("1000.010"));
console.log(formatTimestamp("1000.011"));
console.log(formatTimestamp("1000.100"));
console.log(formatTimestamp("1000.101"));
console.log(formatTimestamp("1000.110"));
console.log(formatTimestamp("1000.111"));
console.log(formatTimestamp("300"));
console.log(formatTimestamp("10.202"));
console.log(formatTimestamp("0.500"));