Needs more testing to be sure but I know that closing fedra normally with alt F4 saves your timelines properly. If you update the program however or it crashes, your open timelines do not save. Oddly enough this can sometimes fail to be the case, like I have updated fedra before and timelines were properly saved, but mostly they don't. I don't know if the timelines just add themselves to the user config when they're opened. If not, maybe that's what should happen instead of saving that info only on exit.
Needs more testing to be sure but I know that closing fedra normally with alt F4 saves your timelines properly. If you update the program however or it crashes, your open timelines do not save. Oddly enough this can sometimes fail to be the case, like I have updated fedra before and timelines were properly saved, but mostly they don't. I don't know if the timelines just add themselves to the user config when they're opened. If not, maybe that's what should happen instead of saving that info only on exit.