Execution of hook $GLOBALS['TYPO3_CONF_VARS']['EXTCONF']['ke_search']['modifyPagesIndexEntry'] is skipped, if the current page has no tt_content records. This makes it impossible to hook empty pages.
But empty pages need to be hooked if you for example try to implement correct content_from_pid handling.
Execution of hook
$GLOBALS['TYPO3_CONF_VARS']['EXTCONF']['ke_search']['modifyPagesIndexEntry']is skipped, if the current page has nott_contentrecords. This makes it impossible to hook empty pages. But empty pages need to be hooked if you for example try to implement correctcontent_from_pidhandling.