If anyone else is having trouble completing the Honest Hearts DLC quest "Rite of Passage" because the Datura potion's visual effects make the game crashy on modern GPUs... Temporarily turn off all fullscreen effects (gameLauncher→Options→ScreenEffects→None) and that will get you past the hallucinogenic parts... :) Once you complete the quest and Whitebird gives you your reward, you can turn them back on again.