Anyone else having a problem with WS2815 lighting up red when only 12v and GND connected

Bought a 5 meter WS2815, i thought it would not light up at all if i only fed power to it and no signal. It had originally around 30 leds from the beginning of the strip to light up red when fed with power, the rest were not lighting up, just as i predicted the whole strip would behave. Then i decided to cut the strip right where the last red was lighting up, thinking that there was something wrong with them.
But now i have a strip that has 3 more leds lighting up from where i cut it, and im afraid of cutting those 3 leds off the strip in case the problem isnt there.

When i give it a 5v signal through using wled on esp-01, everything normal, all of the red leds give a right color on everything and every effect works perfect, except that those red leds always return back to red when they should not give any light output. Even when i turn wled Power “off”, those 3 leds remain red.

Also i separated one single led from the first part of the strip that was red previously, and now when i only give that one power, it turns yellow? Very weird. The rest of the leds turn red as they did originally from those first 30, still every effect and color works perfect, just feels like for some reason “off” means “red” for them.

In general electronics really do not like a floating input (dont know if that the English term for it)
The circuit in case will start to act weirldy. Either have a signal or tie it to ground (depending on the circuit in question)

So it broke when i first connected the power without signal? There should be a circuit that makes sure the signal is going through before the power goes on?