A couple of days back, OnePlus released OxygenOS 4.5.11 update for OnePlus 5 with a number of bug fixes and September 2017 security patches. Now the team released a bug fixing OxygenOS 4.5.12 update for OnePlus 5. The new update fixes missing app icon bug found in the previous OxygenOS 4.5.11 update. Besides that, the new update includes all the fixes included in the previous update.
OnePlus 5 users who are already updated to OxygenOS 4.5.11 update will receive the new OxygenOS 4.5.12 OTA (over the air) update in the next couple of days. You can also download and install the update (OTA or Full firmware) manually, if you wish so. Check out the below guide for details.
Full changelog of OxygenOS 4.5.12 update for the OnePlus 5:
Fixed bug of missing icon of Download app in 4.5.11
Supports customization of notification ringtone
Improved launching speed of apps
Optimized adaptive brightness
Fixed issue of YouTube video lagging behind audio
Fixed display issues of some UI elements
Fixed issue of no 4G+ network in some regions
Updated Android security patch to September
General bug fixes
If you have not received the OTA update notification for OxygenOS 4.5.12 on your OnePlus 5 yet, check it by going to Settings > About > System Update > Check for update. Alternatively, follow the manual installation guide.
Manual Installation guide (OTA/Full ROM)