How can I prevent a Pixel 6 from changing focus while recording a video with the native camera application?

For example, if I record a video from behind a window, I tried to put the focus on whatever I'm looking it behind the window, but if something happens on the window while I'm recording, such as rain on the window, Pixel 6 may decide to focus on the window, suddenly and at any time. How can I prevent a Pixel 6 from changing focus while recording a video with the native camera application? I use Android 12.