Yeah man, extra foxtailing at the end of the cycle is something that is common in many (landrace) Sativa's as well, it is sometimes also called second internodal (or internode) bloom. But it's nothing bad, just a new part of a flower that needs to ripen again, you can also take it off when trimming, other option is to leave the plants for 2-3 weeks longer, but then the bottom part will get more amber trichomes and the top part with the new foxtails will be clear/milky.
The Euforia is looking nice indeed, well stacked!
Make sure she gets enough nutes, because she can be a hungry lady!