discourse/app/assets/stylesheets/mobile/admin_report_table.scss

.admin-report-table {
  .report-table {
    table-layout: fixed;

    thead tr th {
      font-weight: normal;
      font-size: $font-down-2;
      white-space: unset;
      .sort-button {
        display: none;
      }
    }
  }
}