Yeah, that sounds weird…
I have made a christmas decoration from a matrix of 64 x 64 LEDs using flexible LED panels from AliE (sorry Core but you don’t have them and your alternatives are way too expensive); and controlling them with WLED software running on a ESP32-S3. This is running well.
Final step is to mount the panel on the design of the screen door just outside the front door (a few cable ties should do that job) and run 5V power from inside the livingroom, through the closed front door and screen door, to the LED decoration.
The power itself shouldn’t be a big deal. Each 16 x 16 LED panel is rated 5V 75W (but I expect not to go over 30% brightness). They are connected in 4 strings (1024 LEDs per string), each running off a separate 5V power supply.
Did I mention that I am renting, and cannot damage either the door or other fittings and fixtures - so no drilling holes 
Option 1: I purchased 4 of 2m USB power cables thinking to squeeze them between the door and door frame … however with the outer plastic sheathing, that is still looking a bit thick … so maybe there is a better option.
Option 2: I also purchased some 3pin 22AWG 60cm extension cables to go between the microcontroller and the LED panels. I could position the MCU inside and run four of the 3-wire ribbons through the door cracks - however I’m not sure that 60cm cables will be long enough.
Option 3: Going on the ribbon cable theme, standard ribbon cable will go through the door gaps with ease. We already use standard ribbon cable for the 5V associated with i2c and other sensors … but maybe the current to power 1024 LEDs may be a bit much for thin wire. Would it be feasible to connect the +ve wire from the USB cable to 2 wires in the ribbon cable ? Not a problem to use 3 or 4 ribbon cable wires per power source. And all the GND’s will need to be tied together anyway.
Option 4: I think that I could get away with a small grove cut from the top corner of the doors.
Option 5: There is probably another alternative I haven’t considered.
Thanks for your consideration.
