$newline never
$forall category <- activeCategories
  <div .category>
    <input type=checkbox id=#{checkedIdent category} :elem category checkedCategories:checked>
    <label for=#{checkedIdent category}>
      _{category}

    <fieldset uw-interactive-fieldset data-conditional-input=#{checkedIdent category} .interactive-fieldset--target>
      $forall optIx <- categoryIndices category
        ^{cellWdgts ! optIx}

      $maybe addWdgt <- addWdgts !? (1, (EnumPosition category, 0))
        ^{addWdgt}