Documentation Wonderful Launcherfrequent-errors
Missing Plugin Module Warning Is Not Always Fatal
Why 5,159 telemetry events marked as fatal were usually plugin import noise, not full launcher crashes.
Telemetry snapshot queried on April 17, 2026: 5,159 events across 76 installs for comfyui_fatal_error_detected.
What telemetry shows
- This was the single largest telemetry bucket in the snapshot.
- Most events behaved like plugin-scoped import warnings rather than hard startup failures.
- The common pattern was that ComfyUI came up, but one custom node or optional feature was unavailable.
What users usually notice
- Logs contain
No module named ...while the launcher still reaches the ready state. - Only the workflow that uses the missing node fails.
- The word "fatal" in logs makes the whole environment look broken even when it is not.
What to do next
- Find the missing package or plugin name in the log.
- Decide whether the plugin is actually required for the workflow you are running.
- If it is required, install the documented dependency in the same ComfyUI environment and restart.
When it is safe to ignore
- The launcher is ready and the missing plugin is not used by your workflow.
- The warning describes an optional backend with a known fallback path.
Escalate when
- ComfyUI never becomes ready after the warning.
- The missing node is mandatory for the workflow and there is no fallback.