One UI update quietly blocks Substratum/Swift Installer on the Samsung Galaxy S8/Galaxy Note 8
Back when the first Android P Developer Preview was first released, there was a lot of controversy among enthusiasts about the latest version blocking custom overlays (themes) from being installed. Enthusiasts hoped that this was a bug but, it was confirmed by Google to be a security measure. Since the code responsible for blocking custom overlays is part of AOSP, the Android Pie builds that OEMs have released should also eventually have these patches. Oddly, the One UI (Android Pie) beta and stable updates for the Samsung Galaxy S9, Galaxy S9+, and Galaxy Note 9 does not have this restriction in place. For some reason, however, the beta One UI builds for the Snapdragon and Exynos Samsung Galaxy S8 and Galaxy Note 8 have this restriction in place, blocking users from installing custom overlays from apps like Substratum or Swift Installer.
According to the developers of Swift Installer, the Exynos Samsung Galaxy S8 and Galaxy Note 8 were the first to get these restrictions. In the official Telegram group for Swift, one of the developers posted a FAQ list to answer any specific questions users might have about these new changes.
Unfortunately, this FAQ is outdated since we also noticed that the official One UI beta for the Snapdragon Samsung Galaxy S8 also has these changes. The reason this is surprising to us is that the earlier leaked builds of One UI for the Snapdragon Galaxy S8 and Galaxy Note 8 still allowed custom overlays to be installed, meaning Swift Installer and Substratum were still usable. To confirm this change, I took my Snapdragon Samsung Galaxy S8 and tried to install a theme that was already compiled and installed on my the Snapdragon Samsung Galaxy Note 9. The error below is the same error you get if you were to attempt to install a theme on the Google Pixel 3 running Android 9 Pie.
We aren’t sure why this restriction is only affecting the Galaxy S8 and Galaxy Note 8, especially since the build dates for the Galaxy S8 One UI beta I tested predates the build date for the latest One UI build for the Galaxy Note 9 (January 21 versus January 31). This news really puts a damper on the theming community that Samsung has had. The official Samsung theme store really limits what’s possible with custom themes. Most themes will still work with Substratum given you are rooted, but many users will be unwilling to root their device.