Credit: Travel + Leisure / Getty Images Need to Know One TikToker came up with a creative hack to nap on planes without using a neck pillow.  A sleep medicine physician says that it isn’t dangerous for most travelers, but that it can cause harm to certain passengers.  Shop five supportive neck pillows, like the Ostrichpillow Go Pillow or the Napfun Pillow , to get more restful sleep on planes, from $16.  If you’ve ever had your head bobble an entire flight because you left your neck pillow at home, you know just how necessary they are. But it can be annoying to carry yet another travel accessory around, so one TikToker came up with a creative hack to get better sleep on flights without a pillow. The viral trick involves tucking a scarf into the tight space between your head pillow and seat and tying it below your chin to keep your head from falling forward.  While it’s not something that she would consider dangerous, sleep medicine physician Saema Tahir, M.D.…