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Issues in this state are in scope for a future release. The target release may not have been determined yet. Generally higher-priority items will worked on first. The committers will take our best guess on the initial priority of issues, but the priority may be increased or decreased based on input we receive (votes, comments) from the community.
Issues that are not yet assigned can be worked on by anyone in the community. Attaching a good quality patch to an open issue is the best way to vote 
In Progress
This state means a developer is currently working on the issue. Small issues will usually bypass the review step and be Closed (and resolved as "Fixed") once the changes are committed to trunk and pass automated tests. Larger issues will be moved to the "In Review" state at the discretion of the developer.
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