Widget Builder filter search fields are strange

Environment

Steps to Reproduce

Go to create a widget. Select "Errors". Go to "Filter down your search". project_id, projectID, project.slug are all available, even though "Project" is a global filter for the dashboard. "Environment" is not available. "Release" is available, including its sub-fields like release.build and release.stage, even though "Release" is a top-level dashboard filter.

Same applies to "Transactions". For "Releases", the situation is even stranger. The only available search keys are "environment", "project", and "release". All of those are top-level filters! Also, abnormal_mechanism and sdk are not available, even though those tags are ostensibly added to the metrics.

"Issues" seem to work more correctly. Project and environment are not available keys. Release is, though!

Probably I am misunderstanding something, but this is pretty confusing!

Expected Result

The available filter tags in the search do not overlap with the global selection filters for the dashboard. Also, all available tags are present.

Actual Result

The available search keys overlap (or not) in strange ways with the global selection filters.

getsentry / sentry