Search multiple namespaces or projects in search filter
Problem to solve
It's only possible to search either the entire instance or a single namespace or project. Sometimes you don't have global search enabled for your instance (since you are only indexing a subset of groups or projects) and so global search is not applicable but then also single namespace search is also not very helpful if you have multiple namespaces you are trying to search.
Allow filtering by multiple namespaces or projects instead of just one.