Hi Valerio,
I'd probably do one of two things: either have two tabs open, one to view the problem in the Library Browser, and the other to edit it from the File Manager; or, create a testing set in which to view the problem which is just assigned to you and which serves no other purpose than to hold the problem(s) on which you're working. I usually do the latter, for whatever that's worth.
Gavin
WeBWorK Main Forum
edit/view a new problem
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