I'm not a coder myself, but maybe somebody with some extra spare time can have a look at the following upgrade status output to make the module work with drupal 11.

Problem/MotivationThe module is not ready for drupal 11. I ran upgrade_status on the module with the following results:

================================================================================Flag, 8.x-4.0-beta4Scanned on zo 05/12/2024 - 14:22FILE:\flag\src\Controller\FlagListBuilder.phpSTATUS LINE MESSAGE--------------------------------------------------------------------------------Fix later 53 Call to deprecated function user_roles(). Deprecated in drupal:10.2.0 and is removed from drupal:11.0.0. Use Drupal\user\Entity\Role::loadMultiple() and, if necessary, an inline implementation instead.--------------------------------------------------------------------------------FILE: \flag\src\Form\FlagFormBase.phpSTATUS LINE MESSAGE--------------------------------------------------------------------------------Fix later 350 Call to deprecated function user_roles(). Deprecated in drupal:10.2.0 and is removed from drupal:11.0.0. Use Drupal\user\Entity\Role::loadMultiple() and, if necessary, an inline implementation instead.--------------------------------------------------------------------------------FILE:\flag\src\Plugin\views\relationship\FlagViewsRelationship.phpSTATUS LINE MESSAGE--------------------------------------------------------------------------------Fix later 148 Call to deprecated function user_roles(). Deprecated in drupal:10.2.0 and is removed from drupal:11.0.0. Use Drupal\user\Entity\Role::loadMultiple() and, if necessary, an inline implementation instead.--------------------------------------------------------------------------------FILE:\flag\tests\src\Functional\AdminUITest.phpSTATUS LINE MESSAGE--------------------------------------------------------------------------------Check manually 188 Relying on entity queries to check access by default is deprecated in drupal:9.2.0 and an error will be thrown from drupal:10.0.0. Call \Drupal\Core\Entity\Query\QueryInterface::accessCheck() with TRUE or FALSE to specify whether access should be checked.--------------------------------------------------------------------------------Check manually 204 Relying on entity queries to check access by default is deprecated in drupal:9.2.0 and an error will be thrown from drupal:10.0.0. Call \Drupal\Core\Entity\Query\QueryInterface::accessCheck() with TRUE or FALSE to specify whether access should be checked.--------------------------------------------------------------------------------FILE: modules/contrib/flag/flag.info.ymlSTATUS LINE MESSAGE--------------------------------------------------------------------------------Check manually 3 Value of core_version_requirement: ^9.1 || ^10 is not compatible with the next major version of Drupal core. See https://drupal.org/node/3070687.--------------------------------------------------------------------------------FILE: modules/contrib/flag/modules/flag_bookmark/flag_bookmark.info.ymlSTATUS LINE MESSAGE--------------------------------------------------------------------------------Check manually 3 Value of core_version_requirement: ^9.1 || ^10 is not compatible with the next major version of Drupal core. See https://drupal.org/node/3070687.--------------------------------------------------------------------------------FILE: modules/contrib/flag/modules/flag_count/flag_count.info.ymlSTATUS LINE MESSAGE--------------------------------------------------------------------------------Check manually 3 Value of core_version_requirement: ^9.1 || ^10 is not compatible with the next major version of Drupal core. See https://drupal.org/node/3070687.--------------------------------------------------------------------------------FILE: modules/contrib/flag/modules/flag_follower/flag_follower.info.ymlSTATUS LINE MESSAGE--------------------------------------------------------------------------------Check manually 3 Value of core_version_requirement: ^9.1 || ^10 is not compatible with the next major version of Drupal core. See https://drupal.org/node/3070687.-------------------------------------------------------------------------------- Proposed resolutionFix these small problems so that the module can be used on drupal 11 installs.