Please add a choice under the auto power off feature to set to never.  Or at minimum make the OA3 always stay on when connected to external power.  
My main use of this camera is in aerial videography and photography where the camera is mounted remotely on a wing strut of the airplane.  Camera is controlled via wifi using the MIMO app. The camera must be turned on prior to taking off and must remain on and available for up to three hours per flight.  Power is supplied to the camera by a very long USB-C cord plugged into a USB power socket in the cabin of the aircraft.  So either of the requested features would be fine.  

lts see the C/p  post we get  am with you on it, been asked  before, and still waiting

Hi there. Thank you for reaching out. Currently, this function is unavailable due to compatibility issues but we'll forward this feedback to our developers. After the evaluation of the engineers, significant suggestions or requests will be implemented via the firmware update, app update, etc. For any updates, please stay tuned to the latest news on our DJI official website at www.dji.com. Thank you for your valued support.

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Sorry, I guess I asked about this already.  

You could always set the screen to never turn off after you have powered it on.

johansenfoto Posted at 1-6 10:02
You could always set the screen to never turn off after you have powered it on.

good morning, I wanted to know if even in your osmo action 3 the audio is not heard when you watch the videos directly from the camera.

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Audio does not have a Mute, you buy an aftermarket adapter and do not plug a mic in to mute.  
15 minute timer is there a way to trick it to stay on standby while on by rec/stop every 12 minutes. I suggest another camera, like gopro till DJI can offer the feature since 2018

fans99ecf044 Posted at 1-6 10:25
good morning, I wanted to know if even in your osmo action 3 the audio is not heard when you watch the videos directly from the camera.

Think there is sound on mine

osmonauta Posted at 1-6 10:57
I believe you can only set it to "Never" during recording.

That's true.
And it's really a great feature.

Hi, skysailor64. Thank you for reaching out and sharing your experience. We'd like you to know that we appreciate your valuable suggestions. We will forward your concern to our related department. Thank you for your understanding and support.

This a thousand. Im in a band and I rig cams up before we play and need to be able to control them remotely after doors open. Can’t do anything if it turns off. It’s almost a dealbreaker.

max allowed 30 minute on tehir latest, they never listen just hear

I would require this for my cycling. there is nothing more depressing than to hear than the happy shutting down tone as you nearly finish an assent, during a personal best! The camera should stay on until the battery dies or the memory card is full! Otherwise it's not an action camera!