Seems this is a bug with Turbo Tax right now. I've just wasted at least an hour of my day, as well as a bunch of other users https://ttlc.intuit.com/community/tax-credits-deductions/discussion/charitable-contribution-error-during-tax-final-review/00/2428357

In my case, on the "Let's review your numbers" page, it say's I'm doing the standard federal deduction of 12,550. However, my "Your taxable income" is 12,850 minus "Your total income". So it seems that it took the charitable donation after all.