Using incorrect formatting in FText does not cause compilation errors in EnsureMsgf as it does in other functions such as UE_LOG. This causes crashes to sneak through such as a crash on ensure when in a shipping build if using %s for an FName variable.
Regression?: No
This happens in 4.17 and was reported in 4.13
FName hello("hello"); ensureMsgf(false, TEXT("I will compile and crash at runtime %s"), hello);
To continue and reproduce the crash (A source build is required to edit the necessary files)
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-55681 in the post.