How to stop windows from snapping to side and reducing size?

when my Firefox window is active on Macbook Air Sequoia 15.7.3 if I open a second app, calculator for example, the Firefox window reduces in size and snaps to the side of… (kàsi)

when my Firefox window is active on Macbook Air Sequoia 15.7.3 if I open a second app, calculator for example, the Firefox window reduces in size and snaps to the side of the screen. I want that behavior to stop. I want the calculator to overlay the full size Firefox window. How to achieve that?

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