Can be reproduced with a platform with only:

• agildashboard
• git
• docman

Installed & activated

2022/03/16 16:37:47 [error] 633#633: *4 FastCGI sent in stderr: "PHP message: PHP Fatal error:  Uncaught TypeError: PluginFactory::isPluginAvailable(): Argument #1 ($plugin) must be of type Plugin, bool given, called in /usr/share/tuleap/src/common/Project/XML/ConsistencyChecker.php on line 66 and defined in /usr/share/tuleap/src/common/Plugin/PluginFactory.php:332
Stack trace:
#0 /usr/share/tuleap/src/common/Project/XML/ConsistencyChecker.php(66): PluginFactory->isPluginAvailable()
#1 /usr/share/tuleap/src/common/Project/Registration/Template/ScrumTemplate.php(126): Tuleap\Project\XML\ConsistencyChecker->areAllServicesAvailable()
#2 /usr/share/tuleap/src/common/Project/Registration/Template/TemplateFactory.php(110): Tuleap\Project\Registration\Template\ScrumTemplate->isAvailable()
#3 /usr/share/tuleap/src/common/Project/Registration/ProjectRegistrationPresenterBuilder.php(96): Tuleap\Project\Registration\Template\TemplateFactory->getValidTemplates()
#4 /usr/share/tuleap/src/common/Project/Registration/ProjectRegistrationController.php(83): Tuleap\Project\Regis" while reading upstream, client: 172.22.0.1, server: tee-test.example.com, request: "GET /project/new HTTP/2.0", upstream: "fastcgi://127.0.0.1:9000", host: "tee-test.example.com", referrer: "https://tee-test.example.com/"