Try running the Neopixels off a LiPo battery - that's the easiest way to test. The ~4v voltage still works fine with the pixels but the voltage allows the 3.3v signal from the Pico to get through correctly.
Also worth checking - are the grounds of the two power sources connected? That's another potential culprit of the first green LED.
While 1v94 may work for you, in the ~18 months since that version other people have used Neopixels with Espruino Pico (me included - I just did exactly that with a Pico running 2v01 to make sure yet again) and it works absolutely fine.
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
Try running the Neopixels off a LiPo battery - that's the easiest way to test. The ~4v voltage still works fine with the pixels but the voltage allows the 3.3v signal from the Pico to get through correctly.
Also worth checking - are the grounds of the two power sources connected? That's another potential culprit of the first green LED.
While 1v94 may work for you, in the ~18 months since that version other people have used Neopixels with Espruino Pico (me included - I just did exactly that with a Pico running 2v01 to make sure yet again) and it works absolutely fine.