Wiring up 5+ meters of LED strips powered through USB
Provide the power at both ends. Or in the middle.



The parallel connection of a larger gauge wire will reduce the voltage droop from the FPC significantly.

Your problem though, seems to be that you are greatly overloading your power supply. 130 WS2812 rgb leds at full white take 60mA each meaning you are trying to pull 7.8 Amps through a 1 or 2 amp power supply. The voltage droop you are seeing is from overloading the power supply AND the resistance of the FPC.