cubicweb #1937850 _cwsgid pollutes session data [open]

eg go to user /system preference. Reload the page a bunch of time. Go to /info to view open sessions and their data. You'll see that the 'changes applied' message is there as many times as you've reloaded the page

prioritynormal
typebug
done in<not specified>
load0.300
load left0.300
closed by<not specified>