How do I catch this when it only happens for some players?

Capture it automatically from the player's device with the full stack trace, the device and OS, the build, and a breadcrumb trail of what they did. That turns a vague complaint into a specific, reproducible issue you can fix without owning the hardware it happens on.

How to Fix a Singleton Accessed During Shutdown After It Was Already Destroyed

Q: What causes a singleton accessed during shutdown after it was destroyed?

On application quit, systems tore down in an arbitrary order, so one system called into a singleton that had already been destroyed, producing null reference or invalid-access errors during exit.

Quick answer: Set a shutting-down flag when teardown begins and have singleton accessors return null or no-op once it is set, so late shutdown calls do not touch a destroyed manager.

Shutdown ordering is as fraught as startup ordering. A system that calls a singleton during quit can hit it after it was destroyed, throwing errors right as the game exits.

How to fix it

1. Track a shutting-down flag

Set a static isShuttingDown when application quit begins, and have singleton accessors check it so callers can detect teardown instead of dereferencing a dead object.

2. No-op late calls

During shutdown, have managers ignore work requests rather than executing against partially torn-down state, avoiding errors on the way out.

3. Define a teardown order

Tear systems down in the reverse of their initialization order so dependents stop before the managers they rely on are destroyed.

Catching the ones you can't reproduce

The hardest version of this to fix is the one you can't reproduce — it only happens on a player's hardware, OS, driver, or save state, under conditions that simply aren't present on your machine. A report that says “it crashed” or “it froze” gives you nothing to act on, so the bug survives release after release while quietly costing you players.

Automatic error capture closes that gap. Each failure arrives with its full stack trace, the device and OS, the build number, and a breadcrumb trail of what the player did right before it broke, so even a failure you have never seen becomes a specific, reproducible issue. Fold identical failures into one signature ranked by how many players each hits, and your worklist sorts itself worst-first instead of arriving as a stream of vague complaints.

This is where a tool like Bugnet earns its place. Its SDK captures every error automatically with the full stack trace plus device, OS, memory, build, and game-state context, folds duplicates into one grouped issue with an occurrence count, and ties each to the build it first appeared on — so you fix the problem that hurts the most players first and confirm it is gone when its signature disappears from the next release.

Ship the fix, watch the signature disappear from the next build. That's how you know it's really gone.