Deprecation: #99810 - "versionNumberInFilename" option now boolean

See forge#99810


The system-wide setting $TYPO3_CONF_VARS['FE']['versionNumberInFilename'] was previously evaluated as a "string" value, having three possible options:

  • ""
  • "querystring"
  • "embed"

Depending on the option, resources used in TYPO3's frontend templates, such as JavaScript or CSS assets, had their "modification time" in either the querystring (myfile.js?1675703622), or in the file name itself myfile.1675703622.js - the "embed" option). The latter option required a .htaccess rule.

This existing feature ("cachebusting") is especially important for proxy / CDN setups.

For the sake of simplicity, the option is now a boolean option - and behaves similarly to the backend variant $TYPO3_CONF_VARS['BE']['versionNumberInFilename'].


If the option is now set to "false", it behaves as "querystring" did before, setting it to "true", the feature behaves exactly as "embed". The original empty option is removed, so all assets within the TYPO3 frontend rendering always include cachebusting, by default a querystring, which is fully backwards-compatible.

Affected installations

TYPO3 installations that have actively set this option in LocalConfiguration.php, AdditionalConfiguration.php or in an extension ext_localconf.php.


When updating TYPO3 and accessing the maintenance area, an explicitly set option is automatically migrated. If this is not possible - for example, configuration in AdditionalConfiguration.php is set - the value is always migrated on-the-fly when the setting is evaluated.