How to find what template is causing an error when the error and trace don't say?

I'm getting the typical NG02200: Cannot find a differ supporting object '[object Object]' of type 'object'. error. The issue is, the error was caused by code written by someone else a while ago, and I have no idea what component/template is causing the error.

If I look at the stack trace, there is no mention of a specific component or template; only frames of internal Angular stuff:

Subject.js:34 ERROR RuntimeError: NG02200: Cannot find a differ supporting object '[object Object]' of type 'object'. NgFor only supports binding to Iterables, such as Arrays. Did you mean to use the keyvalue pipe? Find more at https://angular.io/errors/NG02200
at NgForOf.ngDoCheck (common.mjs:3117:31)
at callHookInternal (core.mjs:4024:14)
at callHook (core.mjs:4055:9)
at callHooks (core.mjs:4006:17)
at executeInitAndCheckHooks (core.mjs:3956:9)
at refreshView (core.mjs:13513:21)
at detectChangesInView (core.mjs:13663:9)
at detectChangesInEmbeddedViews (core.mjs:13606:13)
at refreshView (core.mjs:13522:9)
at detectChangesInView (core.mjs:13663:9)


If I set an exception breakpoint to catch it in the act, I get a longer trace, but it still only show internal frames:

find (core.mjs:30705)
ngDoCheck (common.mjs:3109)
callHookInternal (core.mjs:4024)
callHook (core.mjs:4055)
callHooks (core.mjs:4006)
executeInitAndCheckHooks (core.mjs:3956)
refreshView (core.mjs:13513)
detectChangesInView (core.mjs:13663)
detectChangesInEmbeddedViews (core.mjs:13606)
refreshView (core.mjs:13522)
detectChangesInView (core.mjs:13663)
detectChangesInComponent (core.mjs:13638)
detectChangesInChildComponents (core.mjs:13676)
refreshView (core.mjs:13548)
detectChangesInView (core.mjs:13663)
detectChangesInEmbeddedViews (core.mjs:13606)
refreshView (core.mjs:13522)
detectChangesInView (core.mjs:13663)
detectChangesInEmbeddedViews (core.mjs:13606)
refreshView (core.mjs:13522)
detectChangesInView (core.mjs:13663)
detectChangesInComponent (core.mjs:13638)
detectChangesInChildComponents (core.mjs:13676)
refreshView (core.mjs:13548)
detectChangesInView (core.mjs:13663)
detectChangesInComponent (core.mjs:13638)
detectChangesInChildComponents (core.mjs:13676)
refreshView (core.mjs:13548)
detectChangesInView (core.mjs:13663)
detectChangesInComponent (core.mjs:13638)
detectChangesInChildComponents (core.mjs:13676)
refreshView (core.mjs:13548)
detectChangesInView (core.mjs:13663)
detectChangesInEmbeddedViews (core.mjs:13606)
refreshView (core.mjs:13522)
detectChangesInView (core.mjs:13663)
detectChangesInEmbeddedViews (core.mjs:13606)
refreshView (core.mjs:13522)
detectChangesInView (core.mjs:13663)
detectChangesInComponent (core.mjs:13638)
detectChangesInChildComponents (core.mjs:13676)
refreshView (core.mjs:13548)
detectChangesInternal (core.mjs:13437)
detectChanges (core.mjs:13954)
tick (core.mjs:28735)
(anonymous) (core.mjs:28895)
invoke (zone.js:368)
onInvoke (core.mjs:11083)
invoke (zone.js:367)
run (zone.js:129)
run (core.mjs:10934)
next (core.mjs:28894)
next (Subscriber.js:91)
_next (Subscriber.js:60)
next (Subscriber.js:31)
(anonymous) (Subject.js:34)
errorContext (errorContext.js:19)
next (Subject.js:27)
emit (core.mjs:10670)
checkStable (core.mjs:11002)
onHasTask (core.mjs:11100)
hasTask (zone.js:422)
_updateTaskCount (zone.js:443)
_updateTaskCount (zone.js:272)
runTask (zone.js:190)
drainMicroTaskQueue (zone.js:581)
invokeTask (zone.js:487)
invokeTask (zone.js:1631)
globalCallback (zone.js:1674)
globalZoneAwareCallback (zone.js:1695)


I have gone through most of these frame looking for a mention of a component name or a fragment of a template, and I can't find anything that looks relevant. There are massive arrays called hostLView that hold a ton of Angular-specific data, but all the mentioned Injectors and Modules are at best used by many components in the app. I've found references to a grandparent component, but that doesn't narrow it down by much.

I tried searching for *ngFor in all the suspect child components, and actually fixed one related issue that hadn't popped up yet, but that didn't fix the main problem.

What debugging techniques can I use to find what component is at fault, or at least get a hint to narrow down my search?

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