diff --git a/lib/private/Files/SetupManager.php b/lib/private/Files/SetupManager.php
index 76959f6f01ea3..f5338112b213f 100644
--- a/lib/private/Files/SetupManager.php
+++ b/lib/private/Files/SetupManager.php
@@ -209,20 +209,6 @@ function ($mountPoint, IStorage $storage, IMountPoint $mount) use ($reSharingEna
 			return $storage;
 		}, 50, $existingMounts);
 
-		$quotaIncludeExternal = $this->config->getSystemValue('quota_include_external_storage', false);
-		$this->storageFactory->addStorageWrapper(Quota::class, function ($mountPoint, $storage, IMountPoint $mount) use ($quotaIncludeExternal) {
-			// set up quota for home storages, even for other users
-			// which can happen when using sharing
-			if ($mount instanceof HomeMountPoint) {
-				$user = $mount->getUser();
-				return new Quota(['storage' => $storage, 'quotaCallback' => function () use ($user) {
-					return $user->getQuotaBytes();
-				}, 'root' => 'files', 'include_external_storage' => $quotaIncludeExternal]);
-			}
-
-			return $storage;
-		}, 50, $existingMounts);
-
 		$this->storageFactory->addStorageWrapper('readonly', function (string $mountPoint, IStorage $storage, IMountPoint $mount) {
 			/*
 			 * Do not allow any operations that modify the storage
@@ -241,6 +227,28 @@ function ($mountPoint, IStorage $storage, IMountPoint $mount) use ($reSharingEna
 		}, 50, $existingMounts);
 	}
 
+	/**
+	 * Some wrapper are inited after BeforeFileSystemSetupEvent, to permit
+	 * custom apps to preventively register their own handler
+	 *
+	 * @param IMountPoint[] $existingMounts
+	 */
+	private function setupCustomizableWrappers(array $existingMounts): void {
+		$quotaIncludeExternal = $this->config->getSystemValue('quota_include_external_storage', false);
+		$this->storageFactory->addStorageWrapper(Quota::class, function ($mountPoint, $storage, IMountPoint $mount) use ($quotaIncludeExternal) {
+			// set up quota for home storages, even for other users
+			// which can happen when using sharing
+			if ($mount instanceof HomeMountPoint) {
+				$user = $mount->getUser();
+				return new Quota(['storage' => $storage, 'quotaCallback' => function () use ($user) {
+					return $user->getQuotaBytes();
+				}, 'root' => 'files', 'include_external_storage' => $quotaIncludeExternal]);
+			}
+
+			return $storage;
+		}, 50, $existingMounts);
+	}
+
 	/**
 	 * Update the cached mounts for all non-authoritative mount providers for a user.
 	 */
@@ -328,6 +336,8 @@ private function oneTimeUserSetup(IUser $user): void {
 			}
 		}
 
+		$this->setupCustomizableWrappers($mounts);
+
 		$userDir = '/' . $user->getUID() . '/files';
 
 		Filesystem::initInternal($userDir);
diff --git a/lib/private/Files/Storage/Wrapper/Quota.php b/lib/private/Files/Storage/Wrapper/Quota.php
index b0ff0117b960f..02518c4e5927b 100644
--- a/lib/private/Files/Storage/Wrapper/Quota.php
+++ b/lib/private/Files/Storage/Wrapper/Quota.php
@@ -58,7 +58,7 @@ private function hasQuota(): bool {
 
 	protected function getSize(string $path, ?IStorage $storage = null): int|float {
 		if ($this->quotaIncludeExternalStorage) {
-			$rootInfo = Filesystem::getFileInfo('', 'ext');
+			$rootInfo = Filesystem::getFileInfo($path, 'ext');
 			if ($rootInfo) {
 				return $rootInfo->getSize(true);
 			}
diff --git a/lib/private/legacy/OC_Helper.php b/lib/private/legacy/OC_Helper.php
index 8e9135b185707..890fcfe9ca486 100644
--- a/lib/private/legacy/OC_Helper.php
+++ b/lib/private/legacy/OC_Helper.php
@@ -187,10 +187,7 @@ public static function getStorageInfo($path, $rootInfo = null, $includeMountPoin
 		if (!$rootInfo instanceof FileInfo) {
 			throw new NotFoundException('The root directory of the user\'s files is missing');
 		}
-		$used = $rootInfo->getSize($includeMountPoints);
-		if ($used < 0) {
-			$used = 0.0;
-		}
+
 		/** @var int|float $quota */
 		$quota = FileInfo::SPACE_UNLIMITED;
 		$mount = $rootInfo->getMountPoint();
@@ -226,7 +223,13 @@ public static function getStorageInfo($path, $rootInfo = null, $includeMountPoin
 		if ($sourceStorage->instanceOfStorage('\OC\Files\Storage\Wrapper\Quota')) {
 			/** @var Quota $sourceStorage */
 			$quota = $sourceStorage->getQuota();
+			$used = $sourceStorage->getSize($path, $storage);
+		} else {
+			$used = $rootInfo->getSize($includeMountPoints);
 		}
+
+		$used = max($used, 0.0);
+
 		try {
 			$free = $sourceStorage->free_space($rootInfo->getInternalPath());
 			if (is_bool($free)) {