Abstain (Normal Melenchonite)
I'm sorry, Antonio. You know I abhor Le Pen, but if I was French I couldn't in good conscience vote for Macron. I don't need to tell you how appalling his economic platform is and how badly it'll hurt French workers. Besides, a Macron Presidency will almost certainly ensure a Le Pen victory in 2022. The forces driving the far-right are only growing stronger under the current paradigm.
An argument that's been brought up to me is that a narrow FBM win will actually give him a stronger mandate, because he could argue that those who voted for him genuinely endorsed his program. In addition, it would make Panzergirl more competitive and guarantee her the status of "official opposition". If he wins in a blowout, instead, it will be clear who he owes his votes to, and it means the left still has a muscle to flex in the future.
The only real hope for the left at this point is to win a majority in the parliamentary election and hope those parliamentarian aren't sellouts like they were under Hollande. I unenthusiastically voted for Clinton in 2016 - a vote I've come to regret. Voting for Macron, to me, is like voting for Clinton. I wouldn't do that again because why vote for something you don't want? Something you know will only make our current situation worse. The French left needs to focus on non-electoral ways to fight, regardless of who wins. I'm warning you now: the far-right's time has arrived; they will be in power soon one way or another. America, the U.K., Hungary, Turkey, and Poland were just the beginning; this will get worse as our current political and economic paradigm continues to ravage our countries.
You can't always get what you want in politics, and since there are really not that many elections in a person's active lifetime, it behooves one to make one's voice heard when one can, even when it is only voting against what wants least. Your attitude is far too defeatist. The far right will not come to power in the U.K. soon, and Hungary and Turkey have been headed in the same direction for a long time. With Macron, a leftist victory in parliamentary elections, and non-electoral action, the French left can hold off the right for five more years, and try again with a Melenchonite candidate.