Starting in August, installing APKs from unverified developers will require a new procedure called Advanced Flow. It involves enabling developer mode, rebooting the device, and waiting 24 hours with biometric verification.
After that, you choose: allow the APK installation for 7 days or indefinitely. The procedure is a one-time process and applies to all versions of Android.
Will the 24-hour wait stop you from installing APKs outside the store?


Will other custom ROMs still allow for sideloading? Like PostmarketOS, e/OS/, LineageOS etc.?
Yes, custom ROMs are not affected, this is just Google bullshit.
Yes, and PostmarketOS isn’t even Android
Right, honestly forgot about that. Not something I use personally, but hear a lot of buzz about. Anyhow, could a good thing be then to support companies like Fairphone, who sells their phones with e/OS/ already installed? I’ll try and recommend it to my friends, if that is the case.