Google is definitely doing away with the Substratum custom themes. We earlier mentioned the Android P Developer Preview was nixing it and looks like the theme engine will be gone for good. These rootless custom themes’ days are numbered as the Android P rolls out. The tech giant has confirmed the restrictions are final and official which means not so good news for hard-core Android community members. Google removed this loophole from the platform so don’t be surprised if you can no longer implement any theme you want.
At first, Android users were only noticing issues on theming of their phones via the Substratum theming engine. As it turned out, it’s not just a bug but more of a permanent condition until some genius devs discover ways around it. There are developers and ordinary users who have demanded for the feature to be added officially that they even signed a petition—more than 11,000 of them.
Google has already responded to the demand and sent out this statement:
We appreciate the feedback and would like to share some background information and clarifications.
The Overlay Manager Service (OMS) is intended for device manufacturer’s use. OMS, in its current form, is not designed to be a generic theming feature — more design considerations will need to be put into it in order to uphold Android platform’s security and product standards for users. Accordingly, OMS has never been advocated as a public developer feature.
Earlier this year a security patch (CVE-2017-13263) was released to OEMs for Android Oreo devices. The patch restricts the installation of overlays to pre-installed or system-signed apps, in response to a legitimate security issue raised in Android Oreo. Android P also includes this critical security patch, so it restricts overlays in the same way as does Android Oreo.
We understand that custom theming is an important capability for some users. We will take your feedback into consideration with any future work in this area.
A simple explanation is that the generic theming feature isn’t designed for the version of the platform. There are many things to consider to ensure security standards are followed. This somehow proves Google is serious to keep things private, safe, and secure that it’s not just letting any modification to be implemented easily. The tech giant sees it as a security loophole that must be fixed and sure they did.
The Overlay Manager Service (OMS) can’t be changed but it allows the device’s look to be modified even without root. You may consider a custom ROM instead if you want themes on your smartphones. So yeah, don’t be surprised again if you see the “Won’t Fix (Intended behavior)” reference. Don’t worry though, Google is working on a better solution. In the Pixel Launcher, you may see a light and dark theme toggle so you can manually choose an option.
The restrictions by Google have been confirmed so if you’re one of the many people that use the Substratum, you may want to look for other ways on how to customize your phone on Android P.