Johnson and Stein ran in 2012 as well and combined for about one percent of the vote. I don’t think they will be a big factor this race as well. Sure, it’s fashionable for people to say they are for them now, but when they get in that booth, most of them will know it’s a wasted vote and will vote for either the Republican or the Democrat.
Unless You’re a Republican living in a state like Massachusetts and you never liked Trump in the first place so you don’t mind throwing your vote away by voting for Johnson.
In most recent Presidential elections, Third Party candidates wind up polling ten times higher than what they wind up getting on election day. I'll be surprised if Gary Johnson gets much more than 1-2% come November, and Stein won't get more than a fraction of one percent.
As for these being wasted votes, if they aren't in swing states, these 1-2% of voters don't count for much anyway.