Ergo + Compat Bugs

## Web Compatibility Bugs

- https://github.com/glimmerjs/glimmer-vm/issues/1593
- Repro: https://github.com/glimmerjs/glimmer-vm/pull/1660
- https://github.com/emberjs/ember.js/issues/20644
- https://github.com/emberjs/ember.js/issues/20642
- Repro: https://github.com/glimmerjs/glimmer-vm/pull/1661
- https://github.com/emberjs/ember.js/issues/20641
- https://github.com/emberjs/ember.js/issues/20643
- https://github.com/glimmerjs/glimmer-vm/issues/1195

## Reactivity Bugs

- https://github.com/glimmerjs/glimmer-vm-issues/issues/4
- Repro: https://github.com/glimmerjs/glimmer-vm/pull/1657

resolved with words

- https://github.com/glimmerjs/glimmer-vm/issues/1630
Solution:
- migrate cleanup / destruction logic to `registerDestructor`
- stop using `@ember/component`

Examples:
- https://github.com/emberjs/ember.js/issues/20707
- Potential Repro: https://github.com/glimmerjs/glimmer-vm/pull/1656

## Parser Bugs

- https://github.com/glimmerjs/glimmer-vm-issues/issues/8

## Completion Bugs / needs implemented (merged RFCs exist already)

aka, not bugs

- element
https://github.com/emberjs/rfcs/blob/master/text/0287-promote-in-element-to-public-api.md
- https://github.com/emberjs/rfcs/pull/1049
- on
https://github.com/emberjs/rfcs/blob/master/text/0997-make-on-built-in.md
- existing implementation has potentially incorrect implementation
https://github.com/emberjs/ember.js/issues/20647
- `on:` (syntax that expands for all modifiers)
- hash
https://github.com/emberjs/rfcs/blob/master/text/0999-make-hash-built-in.md
- method call syntax
- fn
https://github.com/emberjs/rfcs/blob/master/text/0998-make-fn-built-in.md
- array
https://github.com/emberjs/rfcs/blob/master/text/1000-make-array-built-in.md
- tracked-built-ins
https://github.com/emberjs/rfcs/pull/1068
- [ ] https://github.com/glimmerjs/glimmer-vm/pull/1713

In the future

- `prop:`

-------------------------------

Bugs confirmed not in glimmer-vm

- https://github.com/emberjs/ember.js/issues/20786
- not a problem with glimmer-vm, but in this special ember-only behavior: https://github.com/emberjs/ember.js/blob/main/packages/%40ember/template-compiler/lib/plugins/transform-each-track-array.ts#L26
- additional coverage added here: https://github.com/glimmerjs/glimmer-vm/pull/1658