Backport #26490 related: #26012 1. missing project filter on the issue page. 1e76a824bc/modules/indexer/issues/dboptions.go (L11-L15) 2. incorrect SQL condition: some issue does not belong to a project but exists on the project_issue table. f5dbac9d36/models/issues/issue_search.go (L233)  
1e76a824bc/modules/indexer/issues/dboptions.go (L11-L15)
f5dbac9d36/models/issues/issue_search.go (L233)