Small Changes

[izaius]

I had to change two things to make this work:
Automatic systemctl didn't work so I had to call it.
ACTION=="add", SUBSYSTEM=="usb", ATTR{idVendor}=="1a86", ATTR{idProduct}=="7523", RUN+="/bin/systemctl --no-block start octoprint_usb_autoconnect.service"

The command issued didn't work so I used this. It may be unique to Klipper.
curl -siL -X POST -H "Content-Type: application/json" -H "X-Api-Key: ${APIKEY}" ${OCTOHOST}/api/printer/command -d '{"command":"FIRMWARE_RESTART"}'

[tekdoc]

The above vendor and product id's work with my 2020 Ender 3 non-pro, but just adding FIRMWARE_RESTART to OctoPrint Settings > Printer > GCODE Scripts > After connection to printer is established solves the other problems without any additional modification of the udev rule or the octoprint_usb_autoconnect script.

[skorokithakis]

@izaius's change is what worked for me as well. The command in the README didn't work for me, but this change fixed it. Can it be added to the docs?