TYPO3 Core

There is a bug in core impexp extension that doesn't allow to use export functionality for the non-admin users even when options.impexp.enableExportForNonAdminUser is enabled:

Bug explanation:

EXT:impexp - ImportExportController in the "main" method tries to resolve current page id:

$this->id = (int)($parsedBody['id'] ?? $queryParams['id'] ?? 0);

that always leads to 0 because "id" param is not passed to the mentioned request as it is expected. After that there is a page access check:

$this->pageInfo = BackendUtility::readPageAccess($this->id, $this->permsClause) ?: [];

that always returns empty array for non-admin user because non-admin user can't have access to root page (ID=0) in anyway. As a result we get "You don't have access to this page." error.