Currently we cannot filter for both author and assignee at the same time, so we "fix" it by ignoring author or assignee when we filter on the other (cf 1)

But in the long term it would be cool to fix this, which in itself is a SQL problem:

SELECT issues.*
FROM issues, users 
WHERE issues.project_id = 1
 AND issues.status = 'Opened'
 AND issues.assignee_id = users.id
 AND users."user" = 'fake'
 AND issues.user_id = users.id
 AND users."user" = 'pingou'
ORDER BY issues.id

As can be seen above an user cannot have two (different) names at the same time, so we need to find a way to query it differently.