It's the default for Gmail and I don't know of a way to change it. It's not in the normal settings section.
Here, it just make sure I move important items to another folder, such as something like a "Saved Items" folder.
Sorry.
Hope this helps.
Grif
why is my spam and trash deleting itself and never there? I want to make sure nothing goes there that could be important and it is always empty.

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