_showTimestampTag () {
    if (typeof this.value !== 'number') {
      return false
    }

    const timestampTag = this.editor.options.timestampTag
    if (typeof timestampTag === 'function') {
      const result = timestampTag({
        field: this.field,
        value: this.value,
        path: this.getPath()
      })

      if (typeof result === 'boolean') {
        return result
      } else {
        return isTimestamp(this.field, this.value)
      }
    } else if (timestampTag === true) {
      return isTimestamp(this.field, this.value)
    } else {
      return false
    }
  }
Test whether to show a timestamp tag or not
@return {boolean} Returns true when the value is a timestamp