Users who updated to the most recent Android 7.1.2 build with the February security patches have noticed that certain modifications, such as Substratum Legacy, no longer worked. This is because the update made it so the /vendor partition could not be modified. XDA Senior Member LazorL0rd has posted instructions on how to fix this issue, namely re-flashing the vendor partition via fastboot. Check out the thread for step-by-step instructions!
from xda-developers http://ift.tt/2kMdlNT