Error while running event what-items-do-i-have::on_player_cursor_stack_changed (ID 33)
LuaItemStack API call when LuaItemStack was invalid for read.
stack traceback:
[C]: in function 'index'
__what-items-do-i-have/control.lua:122: in function <what-items-do-i-have/control.lua:117>

Thanks for looking into that!

I can confirm this. When the persistent mode (Shift+Alt+Z) is enabled, picking up a blueprint (does not need to be parameterized), upgrade planner, or deconstruction planner from the blueprint library triggers this error. Picking up planners in inventory does not trigger the error.

Can be "fixed" by changing the code indicated in the error from
item = player.cursor_ghost and player.cursor_ghost.name.name or player.cursor_stack and player.cursor_stack.name
to
item = player.cursor_ghost and player.cursor_ghost.name.name or player.cursor_stack.valid_for_read and player.cursor_stack.name

Fixed for next release