I just finished a fight with one of the major bosses, it ended with an explosion that killed them and downed two party members. Which should be fine, I have two characters up I should be able to help the others, I have healing potions too. But it just started rolling death saves, and because the command to enter turn based mode is unreliable, just outright killed a character without letting me get back into turn based mode to be able to help them back up.
I don't know why turn based mode is so unreliable, I click the button and often nothing happens at all, it just keeps the clock ticking, that should probably be fixed too. But until you can figure that out, a simple fix is possible: don't exit turn based mode if a character is unconscious.