So I found the wallabg2 log. It is in /var/www/wallabag2/var/logs/. I don’t know if it helps but here is one login attempt:
[2024-09-17 15:13:13] app.ERROR: Authentication failure for user "#####", from IP "#######", with UA: "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/128.0.0.0 Safari/537.36". [] []
[2024-09-17 15:13:13] security.INFO: Authentication request failed. {"exception":"[object] (Symfony\\Component\\Security\\Core\\Exception\\BadCredentialsException(code: 0): Bad credentials. at /var/www/wallabag2/vendor/symfony/symfony/src/Symfony/Component/Security/Core/Authentication/Provider/UserAuthenticationProvider.php:89, Symfony\\Component\\Security\\Core\\Exception\\BadCredentialsException(code: 0): The presented password is invalid. at /var/www/wallabag2/vendor/symfony/symfony/src/Symfony/Component/Security/Core/Authentication/Provider/DaoAuthenticationProvider.php:65)"} []
[2024-09-17 15:13:13] security.DEBUG: Authentication failure, redirect triggered. {"failure_path":"/login"} []