The issue only occurs on cypress with a bad request sended to the API:
cypress_runner.js:177015 GET https://tuleap/api/v1/milestones/undefined/milestones?limit=50&offset=0
as result, many erro are thrown in console, and widget does not display empty
VM1507 projectmilestones-19dbd9ad337422fef6e4.js:59113 [Vue warn]: Error in created hook: "Error: `translate-n` and `translate-plural` attributes must be used together:
day to go
."