Add the following search operators:
* /tags?search[post_count_eq]=42
* /tags?search[post_count_not_eq]=42
* /tags?search[post_count_gt]=42
* /tags?search[post_count_gteq]=42
* /tags?search[post_count_lt]=42
* /tags?search[post_count_lteq]=42
Works for all numeric attributes on all index actions.
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