[Bug Report] list_subscriptions plugin prevents the UI from starting with protobuf < 3.20 (Fedora 44)

[aadrian]

Describe the bug:

With the list_subscriptions plugin enabled, opensnitch-ui exits at startup on systems with protobuf older than 3.20, such as Fedora 44 (python3-protobuf 3.19.6).

plugins/list_subscriptions/ui/controllers/rules_attachment_controller.py imports the protobuf code directly:

from opensnitch.proto import ui_pb2 as ui_pb2

All other modules use opensnitch.proto.import_(), which picks proto.pre3200 for protobuf < 3.20. The direct import loads the code generated for newer protobuf versions, which fails, and the UI exits.

This affects the next release 1.9.0: every user with protobuf < 3.20 who enables the plugin. It should be fixed before 1.9.0 is released.

Include the following information:

• OpenSnitch version: master (a135384, 1.9.0)
• OS: Fedora Linux
• OS version: 44 (python 3.14.7, PyQt6 6.11.0, protobuf 3.19.6, grpcio 1.48.4)
• Window Manager: none (reproduced in a container, QT_QPA_PLATFORM=offscreen)
• Kernel version: not relevant (container)

To Reproduce:

1. Build the rpm from master (utils/packaging/ui/rpm/opensnitch-ui.spec) and install it on Fedora 44.
2. Enable the plugin in ~/.config/opensnitch/settings.conf:

   [plugins]
   list=list_subscriptions
   

3. Launch opensnitch-ui.

Without the plugin enabled, the UI starts normally.

Post error logs:

[WARNING][opensnitch-ui:<module>:348] exception: ImportError("cannot import name 'builder' from 'google.protobuf.internal' (/usr/lib/python3.14/site-packages/google/protobuf/internal/__init__.py)")

opensnitch-ui then exits with status 0.

Expected behavior (optional):

The plugin loads with any protobuf version the UI supports, using opensnitch.proto.import_() like the other modules.