Yeah, gas will damage the paint and plastic. Wipe it up immediately, but the damage might already be done.
Fix: Stop the engine and let it cool completely before handling fuel. When refueling outdoors on a level surface, fuel carefully to avoid spills. Do not fill above the upper level mark (red) on the fuel strainer. If you do spill, wipe it up immediately with a clean rag.
If That Didn't Work: Damage caused by spilled fuel is explicitly not covered under the warranty. It's a cosmetic issue, but a good reminder to be extra careful.
Heads Up: Always move the generator at least 10 feet (3 meters) away from the fueling spot before starting it. And remember, the fuel filler cap has a vent lever—keep it OFF for storage/transport and ON to run the engine.