No one can perfectly tell you if water will seep inside your phone or not ,without physical inspection.
You can use the shortcut menus or soft keys for that purpose .
btw we need to use it only while switching the phone on ,right.
becoz most of the work is handled by the gestures and the sensors lift to wake up,
Fingerprint sensor, or assistant menu,,etc.
But my personal opinion don't play with water knowingly because that can damage your phone even if its on perfect condition. IP68 is tested in lab condition so they can handle some splashes only in real world scenarios.
Hope you understood.
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