On top of your preview window, you will find several icons. The fourth from the left is the SPLIT SCREEN VIEW button (a square with a black circel inside).
When you click on this button, you will inactivate it and your effects will become visible.
On the right site of this button you will find a small arrow pointing to the bottom. If you click this one, you will see that you had choosen for the option FX BYPASSED, which makes all your applied FX invisible.
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