I like the dark mode. It is easier on my eyes. If you want to switch you just need to click on the 3 bars at the bottom right of the mobile app and select System Settings. At the bottom of that page is where you can switch from light to dark mode.
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I found it almost immediately after I downloaded the app to begin with.
The same reasons for me to.
I always look to see if an app has a dark mode.
Glad you found it. I assume you also know you can post directly to a group from the main feed as described in the previous poll. You post so much I would think you would know that, 
