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Changes between Version 3 and Version 4 of Ticket #27048, comment 28

v3	v4
8	8	* Post type selection is switched to checkboxes to allow any selection of post types to be selected (including attachments and nav menus)
9	9	* Author, date range and status filters now apply to ''all'' post types being exported
10		* #17379 is fixed as featured images are no longer dropped from posts
11		* #28146 is also fixed as I have included an `export_wp_post_ids` filter in the updated `export_wp()` function
12	10
13	11	I have not included unit tests, partly because (rather ashamedly) I have not learnt how to write them yet, but also because I have merely modified existing functions (most notably `export_wp()` of course), so the existing unit tests for the export code will still cover the same ground as this patch leaving no need for brand new tests.