---
title: "Breaking: #82377 - Option to allow uploading system extensions removed"
manual: "TYPO3 Core Changelog"
version: "main"
permalink: "https://docs.typo3.org/permalink/changelog:breaking-82377"
source: "Changelog/9.0/Breaking-82377-OptionToAllowUploadingSystemExtensionsRemoved.rst"
typo3-version: "9.0"
typo3-major: 9
type: "breaking"
issue: 82377
forge: "https://forge.typo3.org/issues/82377"
tags: ["LocalConfiguration", "FullyScanned"]
rendered: "2026-09-20T18:31:11+00:00"
---

# Breaking: #82377 - Option to allow uploading system extensions removed {#breaking-82377}

See [forge#82377](https://forge.typo3.org/issues/82377)

## Description {#description}

The option to allow uploading additional extensions as system extensions in TYPO3 has been removed
without substitution.

Disclaimer: It is highly discouraged by the TYPO3 Core to modify anything within `typo3/sysext/`,
especially adding extensions, as typo3conf/ is the folder to add or override extensions.

If an administrator needs to do changes within `typo3/sysext/` it's at his/her own risk,
and should not be encouraged to be possible from TYPO3 itself.

## Impact {#impact}

The possibility to upload an extension into `typo3/sysext/` via the Extension Manager / TYPO3 Backend
interface is removed. System extensions can only be added or modified via the file system now.

## Affected Installations {#affected-installations}

TYPO3 instances having the option `$GLOBALS['TYPO3_CONF_VARS']['EXT']['allowSystemInstall']` enabled and do not
run in TYPO3's Composer Mode.

As this option was disabled by default for over 10 years, it is highly unlikely this change will
affect a regular instance.

## Migration {#migration}

The mentioned option, if set, is automatically removed when accessing the Install Tool through
the `SilentMigrationService`.