Core

Example:
phpmyadmin localconf:

$TYPO3_CONF_VARS['EXT']['extConf']['phpmyadmin'] = 'a:4:{s:12:"hideOtherDBs";a:7:{s:3:"cat";s:5:"basic";s:6:"subcat";s:5:"x/10z";s:4:"type";s:7:"boolean";s:5:"label";s:147:"Only show TYPO3 database in pMA: If enabled, only the TYPO3 database is available, otherwise pMA will show all databases the SQL-user has access to";s:4:"name";s:12:"hideOtherDBs";s:5:"value";s:1:"1";s:13:"default_value";s:1:"1";}s:9:"uploadDir";a:7:{s:3:"cat";s:5:"basic";s:6:"subcat";s:3:"x/z";s:4:"type";s:6:"string";s:5:"label";s:182:"Path for database dumps: If starting with a slash it\'s assumed as an absolute path to the directory where the dumps should be saved, otherwise it\'s relative to the TYPO3 installation";s:4:"name";s:9:"uploadDir";s:5:"value";s:21:"uploads/tx_phpmyadmin";s:13:"default_value";s:21:"uploads/tx_phpmyadmin";}s:10:"allowedIps";a:7:{s:3:"cat";s:5:"basic";s:6:"subcat";s:3:"x/z";s:4:"type";s:6:"string";s:5:"label";s:71:"Allowed IPs: Comma separated list of IPs that may access this extension";s:4:"name";s:10:"allowedIps";s:5:"value";s:0:"";s:13:"default_value";s:0:"";}s:12:"useDevIpMask";a:7:{s:3:"cat";s:5:"basic";s:6:"subcat";s:3:"x/z";s:4:"type";s:7:"boolean";s:5:"label";s:80:"Use devIpMask: Use devIpMask from Install Tool (notice: overrules above setting)";s:4:"name";s:12:"useDevIpMask";s:5:"value";s:1:"0";s:13:"default_value";s:1:"0";}}'; // Modified or inserted by TYPO3 Extension Manager.

Word: it\'s
becomes: it's
therefore breaking PHP parsing.

All values must be quoted - or used literally.