This is an annoying behavior and I'm wondering if there is any way to keep it from happening.  I'm using SW2014 SP5.  I have a large-ish assembly and start editing a part directly in the assembly.  Say, for example, I create an extrude.  After the feature has been made, the feature tree will collapse as if I hit the "-" next to the part.  I have to keep expanding it.  It's annoying to have to find the part in the tree and re-expand it so often.  Do other people have this problem?  Is there any work around?