TYPO3 Core

The comment in TSFE for sys_language_contentOL should be fixed
is:

    /**
     * Site content overlay flag; If set - and sys_language_content is > 0 - ,
     * records selected will try to look for a translation pointing to their uid. (If
     * configured in [ctrl][languageField] / [ctrl][transOrigP...]
     * @var int
     */
    public $sys_language_contentOL = 0;

should be:

    /**
     * Site content overlay flag; If set - and sys_language_content is > 0 - ,
     * records selected will try to look for a translation pointing to their uid. (If
     * configured in [ctrl][languageField] / [ctrl][transOrigP...]
     * Possible values: [0,1,hideNonTranslated]
     * This flag is set based on TypoScript config.sys_language_overlay setting
     * 
     * @var int|string
     */
    public $sys_language_contentOL = 0;