['showitem'] Section

This string is used for rendering the form in the user setup module. It contains a comma-separated list of fields, which will be rendered in that order.

To use a tab insert a --div--;LLL:EXT:foo/... item in the list.

Example (taken from typo3/sysext/setup/ext_tables.php):

'showitem' => '--div--;LLL:EXT:setup/Resources/Private/Language/locallang.xlf:personal_data,realName,email,emailMeAtLogin,password,password2,lang,
      --div--;LLL:EXT:setup/Resources/Private/Language/locallang.xlf:opening,startModule,thumbnailsByDefault,titleLen,
      --div--;LLL:EXT:setup/Resources/Private/Language/locallang.xlf:editFunctionsTab,edit_RTE,edit_wideDocument,edit_docModuleUpload,showHiddenFilesAndFolders,resizeTextareas,resizeTextareas_Flexible,resizeTextareas_MaxHeight,copyLevels,recursiveDelete,resetConfiguration,clearSessionVars,
      --div--;LLL:EXT:setup/Resources/Private/Language/locallang.xlf:adminFunctions,simulate,debugInWindow'