HTC 816G downgrade from lolipop to kitkat

hi
i had to root my htc 816g after the lollipop update cuz the small internal memory size and i couldn't even update the soft apps
i used TWRP
i just want to downgrade it to kitkat with the right steps and the right stock
i want to be able to apply the official updates too so can i or i will never be able to since i rooted it before ?!
i don't have enough info about rooting or backing up so pls try to explain

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[REQUEST] Screen Recorder for KitKat

Hello! I don't know if it's in the right section, but I want to request an app for KitKat. I'm not happy with the screen recorders you can find in the market, so wouldn't it be great if someone created a better one? Thanks.

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Xposed installer is always showing not active in my kitkat device

In my rooted andriod kitkat i installed one by one All version of xposed installer is showing currently is not activate please help what i can do

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