This is a short instruction on how to get the Netflix Plugin for Kodi working on a raspberrypi 3 with the current Beta Version 0.14.22. It may be outdated when you read it. Especially have a look at the official testing repo for a currently working version.
First of all you need the inputstream adaptive Plugin installed on your raspberrypi: sudo apt-get install kodi-inputstream-adaptive
The plugin also calls for a python module called cryptodome so install it via pip install --user pycryptodomex for the user you start kodi with. Beware: If you’re using multiple python versions at once, ensure youre installing it with the correct pip (same version as your kodi uses).
No we need the widevine library which decrypts the DRM protected netflix streams. The easiest way of getting it is to install the Widevine Support Plugin as described here. This will automatically download the version suitable for your architecture and also plays a DRM protected Stream as test.
No you can install the netflix plugin. For me only the current Beta Version (direct donwloads) worked. After installing it you can login to netflix and stream a video. The plugin then will upgrade your widevine version from above which will need 2 GB free space on your system during installation (it extracts the library from a chrome OS installation image) and root privilieges which you can grant trhough the installation process.
After this you should be able to watch videos from netflix. However you remain with one issue: Your raspberrypi is not capable of decrypting and watching a 1080p stream simultaneously. So you have to make 720p as default. To do so go to the Settings of your netflix addon > Inputstream Addon Settings > Set both „max resolution“ values to „720p“.
Known errors
I experienced some trouble logging into my account and playing a video. For both problems I found an entry in my log file (~/.kodi/temp/kodi.log) which looks like: route(filter(None, g.PATH.split('/'))) The solution here is to switch your netflix Settings to IPC over HTTP: Settings > Expert > Enable IPC over HTTP. I had to play around with it a bit to make it work so don’t hassitate to turn it on and off at least once and try the failed action in between.