Tip of the Day
Pay attention to the specifics of an achievement - some only count toward the unlock if a drop comes from an activity directly.

Translations:Inventory Space (Mechanics)/2/en

From Walkscape Walkthrough

Items that have the Inventory Space attribute can increase or decrease this soft cap value allowing you to carry additional stacks of items over the normal limit without being overencumbered or causing you to be overencumbered easier.