How to reproduce:
You can take the search tool for example, its result grid is stateful.

• Open the tool, make changes (set #1) on the column (show/hidden, size) and close the tool.
• Open the tool again, changes have persisted. You can make some other changes (set #2) if you want, and the close the tool.
• Open the tool again. Changes of set #1 have not persisted, only changes of set #2.

-> Only the last set of modifications persist, older changes are always lost.