Victoria Song is a senior reporter and author of the Optimizer newsletter. She has more than 13 years of experience reporting on wearables, health tech, and more. Before coming to The Verge, she worked for Gizmodo and PC Magazine. Ten years ago, Dyson kicked off the hair gadget arms race with its $400 Supersonic hairdryer . Today, it’s back with a slightly smaller and cheaper travel-size version. As the name suggests, the $299.99 Supersonic Travel is meant for people on the go — whether that’s a business trip or a jaunt to the gym before work. Dyson claims that it’s 32 percent smaller, 25 percent lighter, and capable of fitting in purses and carry-on luggage. It uses the same basic tech as the Supersonic, though it now automatically adapts voltage to the country you’re in. And folks who already invested in the original Supersonic don’t have to worry about buying new attachments. The new hairdryer is backwards compatible.…