diff --git a/lib/Migration/Version10100Date20260226000000.php b/lib/Migration/Version10100Date20260226000000.php
new file mode 100644
index 0000000000..6ada5909a5
--- /dev/null
+++ b/lib/Migration/Version10100Date20260226000000.php
@@ -0,0 +1,42 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2026 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Richdocuments\Migration;
+
+use Closure;
+use OCP\DB\ISchemaWrapper;
+use OCP\Migration\IOutput;
+use OCP\Migration\SimpleMigrationStep;
+use Override;
+
+/**
+ * Widen owner_uid and editor_uid columns from varchar(64) to varchar(255) to support federated cloud IDs
+ */
+class Version10100Date20260226000000 extends SimpleMigrationStep {
+	#[Override]
+	public function changeSchema(IOutput $output, Closure $schemaClosure, array $options): ?ISchemaWrapper {
+		/** @var ISchemaWrapper $schema */
+		$schema = $schemaClosure();
+		$changed = false;
+
+		if ($schema->hasTable('richdocuments_wopi')) {
+			$table = $schema->getTable('richdocuments_wopi');
+			foreach (['owner_uid', 'editor_uid'] as $columnName) {
+				if ($table->hasColumn($columnName) && $table->getColumn($columnName)->getLength() < 255) {
+					$table->changeColumn($columnName, [
+						'length' => 255,
+					]);
+					$changed = true;
+				}
+			}
+		}
+
+		return $changed ? $schema : null;
+	}
+}