---
title: "Important: #81568 - Migrate cHash configuration"
manual: "TYPO3 Core Changelog"
version: "main"
permalink: "https://docs.typo3.org/permalink/changelog:important-81568"
source: "Changelog/9.0/Important-81568-MigrateChashConfiguration.rst"
modified: "2026-09-14T09:47:36+00:00"
---

# Important: #81568 - Migrate cHash configuration

See [forge#81568](https://forge.typo3.org/issues/81568)

## Description

All cHash-related configuration options have been previously migrated on every TYPO3 request
into an array-structured form.

The following cHash-related configuration entries below have been migrated:

-   `$TYPO3_CONF_VARS['FE']['cHashExcludedParameters']` is now an array instead of a
    comma-separated list, and migrated to `$TYPO3_CONF_VARS['FE']['cacheHash']['excludedParameters']`
-   `$TYPO3_CONF_VARS['FE']['cHashOnlyForParameters']` is now an array instead of a
    comma-separated list, and migrated to `$TYPO3_CONF_VARS['FE']['cacheHash']['cachedParametersWhiteList']`
-   `$TYPO3_CONF_VARS['FE']['cHashRequiredParameters']` is now an array instead of a
    comma-separated list, and migrated to `$TYPO3_CONF_VARS['FE']['cacheHash']['requireCacheHashPresenceParameters']`
-   `$TYPO3_CONF_VARS['FE']['cHashExcludedParametersIfEmpty']`

    -   If the old value was `*`, the following parameter is now set to true to the
        option `$TYPO3_CONF_VARS['FE']['cacheHash']['excludeAllEmptyParameters']`
    -   If the old values were a comma-separated list, they are now migrated as an array to
        `$TYPO3_CONF_VARS['FE']['cacheHash']['excludedParametersIfEmpty']`

These values are now migrated as a "silent upgrade wizard" via the Install Tool to the format
that TYPO3 uses internally since several versions.

## Impact

Any values set in `LocalConfiguration.php` are migrated automatically. If any of the options were
overridden in `AdditionalConfiguration.php` these need to be adapted manually.

Changes within extensions are not affected.