Probably not advised because...
Most puzzle venues contain a wide spectrum of solvers; Some young, some old, some who solve in pen, some who pride themselves on solving without ever Googling an answer.
I try to envision the full range of demographics when constructing a puzzle. I especially take note of the last category above -- the no-Google solvers.
Now having said all that, I imagine there may be a specialized venue which contains only tech-savvy solvers, and they might welcome such a puzzle. Or, if a Notepad established that the puzzle would only be solvable via help from the internet, then solvers would be forewarned. But, if more than, say, 20% of the audience would be significantly handicapped by this -- or any other -- requirement, then it would be a hard sell with the editor.