I have a passion and hobby to go through complete literature and review of all iOS releases and needless to say I haven't missed iOS 12.1.3, 12.1.4 12.2, 12.3 & 12.3.1 assessment published on various news media and on Apple web page including leading news magazines (Forbes & Fortune Magazines).
The major takeaways from this iOS 12.3 update is Apple TV, Kids TV, The app is available on Samsung TVs, tvOS has been updated, AirPlay 2, Apple TV app,
And iOS 12.3.1 includes bug fixes for your iPhone and iPad. This update:
- Fixes an issue that could prevent making or receiving VoLTE calls
- Fixes issues in Messages that could cause messages from unknown senders to appear in your conversation list even though Filter Unknown Senders is enabled
- Fixes an issue that could prevent the Report Junk link from appearing in Messages threads from unknown senders
No where I could find any link on the problem of "Screen Recording" faced by you. Introspect and have a complete and thorough check on the way you handle settings on your iPhone.
Read often for a peaceful life.
Solution. Check if it has been restricted using Screen Time.
Settings > Screen Time > Content & Privacy Restrictions > [Enter Screen Time Passcode] > Content Restrictions > Screen Recording > [Allow]