LineageOS Starts Removing Theme Engine Related Code, Basically Confirming CMTE’s Demise
Before the rise of Substratum, there was the CyanogenMod Theme Engine (CMTE). Introduced all the way back with CyanogenMod 9 (based on Android Ice Cream Sandwich), it added system-wide theme capabilities to CyanogenMod builds. With the release of CyanogenMod 14 (which later became LineageOS), CMTE was nowhere to be found. Meanwhile many other popular custom ROMs started to favor the OMS-based Substratum Theme Engine in their builds. And with Android 8.0 Oreo now including native OMS support, it appears that the LineageOS team has now pulled the plug on CMTE for good.
We had already heard from a source some time back that CMTE was basically dead, but there was still a glimmer of hope by some users that it would, someday, return in LineageOS. Alas, that does not seem to be the case: as a part of the LineageOS 15.0 bringup, the guts of the CyanogenMod Theme Engine, as well as all remaining mentions of the theme engine are in the process of being removed from the source. This change was finally committed on October 12th, and basically marks the death of the CyanogenMod Theme Engine.
What’s next for those looking to theme their device? It’s entirely possible, but unlikely, that the LineageOS team will move to develop their own theme engine. Even some OEMs (Samsung, for instance) include support for RRO or OMS, after all.
Substratum has risen in popularity over the years and its theming framework has only gotten better since Sony moved from Runtime Resource Overlays (RRO) to Overlay Manager Service (OMS). As such, Substratum has now replaced CMTE for most custom ROMs out there. What’s more, if you want to theme your Android Oreo device you’re in luck, since Oreo includes support for OMS natively. This means that you will be able to use Substratum without root on any device—including on LineageOS 15.