Defines a field type Block reference which creates a relationship to a block and allows the block to be displayed as the content of the field.
It saves this relationship using the block's Version 2 saves module + delta (
bid, not its delta + module.
moddelta), which is much more robust than
Widget "Select list (with drag-and-drop sort)" has been deprecated. Use Multiple Selects instead!
N.B. Block configuration visibility settings are respected since version 7.x-1.14. If a referenced block does not appear when viewing the node, check the block's visibility settings on /admin/structure/block. Note that visibility settings are evaluated regardless of whether the block is assigned to a region.
Version 2's API has changed completely, so modules using Blockreference might be broken. There is an upgrade path, so content should be fine. You can't go back to 1.x, so back up your data! Test related contrib modules well! They might count on the old data structure. See the release notes for 2.0-beta1.