Problem detected when migrating subflows between machines

[Trying_to_learn]

Error after reconnecting the input wire and deploy.

Switched to FULL DEPLOY

Working.

Go figure.

So should I COMPLETE/SOLVE mark this or leave it open so people in the know may look at it and maybe dig into what happened as there should be better error notification happening.
and the weird fact that I could have two of the same subflow and one makes errors and the second one doesn't.

[GogoVega]

This is a bug. Can you give us a minimalist flow to reproduce the problem?

[Trying_to_learn]

No.
(not being rude. just stating the fact)

What ever the problem is/was has now been fixed when I did the full deploy.

Which is not a good reflection on me for not thinking of doing that.
But....

[Trying_to_learn]

GOOD NEWS / BAD NEWS!

Today I was cleaning up flows. Moving nodes, all that stuff.

The problem is back.

But HOW it was caused.... Dunno.

TO RECAP

It would SEEM that if I (only/simply/even) move a subflow and re-deploy (modified nodes only) the problem can reoccur.

The BIG PROBLEM is there is NOTHING in the messages to identify WHICH ONE.

P.S.

Yesterday doing a FULL DEPLOY fixed the problem.
Though admittedly that was AFTER I found which subflow was causing the problem.....
FULL DEPLOY hasn't worked this time.

[Trying_to_learn]

SUPER URGENT UPDATE!

FOR DEVELOPERS TO READ

Ok, so the story so far:

I am/was/am getting these weird messages of an error with NO identifiable node.
Hinting at a SUBFLOW. (important)

All reports are now for ONE machine.

I got lucky yesterday and discovered it was my MachineHealth V2 subflow.

If it was DISABLED but wires left going INTO it: I got the errors. (Note)
ONLY if I removed the wires did the errors stop!!

I exported the nodes and put them on the flow level. They worked.

If I put a SECOND COPY of the subflow and tested it: IT WORKED!!

Clutching at straws, I put a THIRD copy (left the initial copy else where on the flow) and switched the ORIGINAL one with the THIRD COPY.
Wired it up.
It worked. No errors.

NR 4.0.9.
Node.js 18.20.8
Buster.

So today while tidying up ANOTHER flow on this machine I started getting these errors.

Checked all the subflows I'd moved. NOTHING.

Then - again: on a whim and prayer - I unwired the MachineHealth V2 subflow.

FIXED!

Dragged another one from the left and put it in.
Wired it up.
Deleted the original one.
DEPLOYED.

NO ERRORS.

Sorry, I forget if it was modified nodes or full.
But I suspect modified nodes.

[Trying_to_learn]

AND ANOTHER UPDATE!

(I'm stupid.)

I didn't actually check the subflow. I put it in, the errors stopped.

But....

The subflow is EMPTY!

So - of course - there won't be any errors.

It is not doing anything.

H E L P !

This is what it is supposed to look like - after another export/import from another machine.