The first screen is with oUF_MF version 1.11, the second one with 1.13
The frames in question are spawned through headers. They look so when no changes through MF are done. The frames are not movable as the green area does not appear. I can scale them though, after that the green area is there until I move them. After I stop dragging, the scale resets to the original one and the green area disappears making the frames not movable again.
The names are also a bit strange. Partypets and partytargets are just called "party". For MTtargets it just takes the name of the frame I set in my layout. This is not something introduced in 1.13 though.