diff --git a/CONTRIBUTOR-DOCS/03_project-planning/03_components/README.md b/CONTRIBUTOR-DOCS/03_project-planning/03_components/README.md
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@@ -47,6 +47,7 @@
     - [Button migration roadmap](button/rendering-and-styling-migration-analysis.md)
 - Button Group
     - [Button group accessibility migration analysis](button-group/accessibility-migration-analysis.md)
+    - [Button group migration plan](button-group/migration-plan.md)
     - [Button Group migration roadmap](button-group/rendering-and-styling-migration-analysis.md)
 - Checkbox
     - [Checkbox migration roadmap](checkbox/rendering-and-styling-migration-analysis.md)
diff --git a/CONTRIBUTOR-DOCS/03_project-planning/03_components/button-group/migration-plan.md b/CONTRIBUTOR-DOCS/03_project-planning/03_components/button-group/migration-plan.md
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+<!-- Generated breadcrumbs - DO NOT EDIT -->
+
+[CONTRIBUTOR-DOCS](../../../README.md) / [Project planning](../../README.md) / [Components](../README.md) / Button Group / Button group migration plan
+
+<!-- Document title (editable) -->
+
+# Button group migration plan
+
+<!-- Generated TOC - DO NOT EDIT -->
+
+<details open>
+<summary><strong>In this doc</strong></summary>
+
+- [TL;DR](#tldr)
+    - [Resolved questions](#resolved-questions)
+- [1st-gen API surface](#1st-gen-api-surface)
+    - [Properties / attributes](#properties--attributes)
+    - [Methods](#methods)
+    - [Events](#events)
+    - [Slots](#slots)
+    - [CSS custom properties](#css-custom-properties)
+    - [Shadow DOM output (rendered HTML)](#shadow-dom-output-rendered-html)
+- [Dependencies](#dependencies)
+- [Migration sequencing and prerequisites](#migration-sequencing-and-prerequisites)
+    - [Dependency-aware recommendation](#dependency-aware-recommendation)
+    - [Related components and ordering notes](#related-components-and-ordering-notes)
+    - [User confirmation needed](#user-confirmation-needed)
+- [Changes overview](#changes-overview)
+    - [Must ship — breaking or a11y-required](#must-ship--breaking-or-a11y-required)
+    - [Additive — ships when ready, zero breakage for consumers already on 2nd-gen](#additive--ships-when-ready-zero-breakage-for-consumers-already-on-2nd-gen)
+- [2nd-gen API decisions](#2nd-gen-api-decisions)
+    - [Public API](#public-api)
+    - [Behavioral semantics](#behavioral-semantics)
+    - [Accessibility semantics notes (2nd-gen)](#accessibility-semantics-notes-2nd-gen)
+- [Architecture: core vs SWC split](#architecture-core-vs-swc-split)
+- [Migration checklist](#migration-checklist)
+    - [Preparation (this ticket)](#preparation-this-ticket)
+    - [Setup](#setup)
+    - [API](#api)
+    - [Styling](#styling)
+    - [Accessibility](#accessibility)
+    - [Testing](#testing)
+    - [Documentation](#documentation)
+    - [Review](#review)
+- [Blockers and open questions](#blockers-and-open-questions)
+    - [Design](#design)
+    - [Architecture and behavior](#architecture-and-behavior)
+    - [Scope and prerequisites](#scope-and-prerequisites)
+- [References](#references)
+
+</details>
+
+<!-- Document content (editable) -->
+
+> **Epic SWC-2071** · Planning output. Must be reviewed before implementation begins.
+
+---
+
+## TL;DR
+
+Button group is a simple layout and semantics wrapper for related button actions. The 1st-gen implementation is minimal (flexbox container with size propagation), making the migration straightforward. The core changes are:
+
+- **Rename `vertical` boolean to `orientation` property** (aligns with React Spectrum S2 and Figma); this is the only consumer-facing breaking change.
+- **Add `role="group"`** on the host for WCAG compliance (1st-gen is missing this).
+- **Add `align` property** for button alignment (start/center/end); matches React S2.
+- **Propagate disabled state** from group to children via an optional `disabled` attribute.
+- **Overflow behavior (flex wrapping or auto-switch to vertical)** is documented in React S2 but is not in the Figma design spec; deferred from MVP. Regular flex wrapping may be an acceptable starting point since arrow-key navigation is not managed by button-group.
+- Button group depends on `swc-button` being available in 2nd-gen (already migrated).
+
+### Resolved questions
+
+- ~~Q1~~: XL size **is supported**. React S2 also includes XL. Size S uses an 8px gap; M/L/XL all use the same 12px gap token.
+- Q2 in [Architecture and behavior](#architecture-and-behavior): Overflow behavior deferred from MVP. Regular flex wrapping may be an acceptable starting point.
+
+---
+
+## 1st-gen API surface
+
+**Source:** [`1st-gen/packages/button-group/src/ButtonGroup.ts`](../../../../1st-gen/packages/button-group/src/ButtonGroup.ts)
+**Version:** `@spectrum-web-components/button-group@1.12.1`
+**Custom element tag:** `sp-button-group`
+
+### Properties / attributes
+
+| Property | Type | Default | Attribute | Notes |
+| -------- | ---- | ------- | --------- | ----- |
+| `vertical` | `boolean` | `false` | `vertical` | Reflected. Switches flex-direction to column. |
+| `size` | `ElementSize` (`'s'` \| `'m'` \| `'l'` \| `'xl'`) | none (`noDefaultSize: true`) | `size` | From `SizedMixin`. Propagated to slotted children on change and slotchange. |
+
+### Methods
+
+| Method | Signature | Notes |
+| ------ | --------- | ----- |
+| `manageChildrenSize` | `(slot: HTMLSlotElement): void` | Private. Iterates assigned elements and sets `button.size = this.size`. |
+| `handleSlotchange` | `(event: Event & { target: HTMLSlotElement }): void` | Protected. Calls `manageChildrenSize` on slotchange. |
+
+### Events
+
+None. `sp-button-group` does not dispatch any custom events.
+
+### Slots
+
+| Slot | Content | Notes |
+| ---- | ------- | ----- |
+| default | `sp-button` elements | The buttons that make up the group. Size is propagated to all assigned elements. |
+
+### CSS custom properties
+
+From `button-group.css.ts` (sourced from spectrum-css `spectrum-two` branch):
+
+| Property | Purpose | Notes |
+| -------- | ------- | ----- |
+| `--mod-buttongroup-spacing` | Gap between buttons | Default: `--spectrum-spacing-300`; size S: `--spectrum-spacing-200` |
+| `--mod-buttongroup-justify-content` | Alignment of buttons | Default: `normal` |
+| `--mod-buttongroup-flex-wrap` | Wrap behavior | Default: `wrap` |
+| `--mod-buttongroup-spacing-horizontal` | Horizontal gap (deprecated) | Replaced by `--mod-buttongroup-spacing` |
+| `--mod-buttongroup-spacing-vertical` | Vertical gap (deprecated) | Replaced by `--mod-buttongroup-spacing` |
+
+This full modifier surface will not be carried forward to 2nd-gen.
+
+### Shadow DOM output (rendered HTML)
+
+```html
+<slot></slot>
+```
+
+The component renders only a default slot. All styling is on `:host` and `::slotted(*)`.
+
+---
+
+## Dependencies
+
+| Package | Version | Role |
+| ------- | ------- | ---- |
+| `@spectrum-web-components/base` | 1.12.1 | `SpectrumElement`, `SizedMixin`, Lit, decorators |
+| `@spectrum-web-components/button` | 1.12.1 | Type import only (`Button` type for casting slotted elements) |
+
+---
+
+## Migration sequencing and prerequisites
+
+### Dependency-aware recommendation
+
+**Proceed independently.** Button group's only hard dependency is `swc-button`, which is already fully migrated to 2nd-gen (status table shows Button at all steps complete). Button group does not need to wait on any other component, and no other component depends on it being migrated first.
+
+### Related components and ordering notes
+
+| Component | Relationship | Status |
+| --------- | ------------ | ------ |
+| **Button** (`swc-button`) | Children of button group; must exist in 2nd-gen | **Complete** — fully migrated |
+| **Action Group** (`swc-action-group`) | Similar layout pattern but for action buttons with toolbar semantics | Analyze ✓ only |
+| **Toggle Group** (`swc-toggle-group`) | Separate component for toggle/selection semantics; not this component | N/A (new for S2) |
+
+### User confirmation needed
+
+None. Button group can proceed independently because `swc-button` is already complete and button group does not serve as a base for other components.
+
+---
+
+## Changes overview
+
+> **Priority framing:**
+>
+> - Use the component's full feature/functionality inventory to decide what belongs here; do not classify scope without first identifying the full surface area.
+> - **Must ship** items define the in-scope work required for this migration.
+> - **Additive** items are typically deferred or out of scope for this migration unless the user explicitly pulls them in.
+> - **Additive / deferred** does not mean deprecated or dropped; it usually means not required to meet the baseline 80% consumer-use needs for this migration.
+> - **Accessibility is non-negotiable** — all a11y requirements ship as part of this migration.
+> - **Breaking changes** are assessed on merit — some must ship now to avoid a second, more disruptive migration event later.
+> - **Additive changes** can be deferred and will not cause consumer breakage when they do ship.
+
+### Must ship — breaking or a11y-required
+
+#### API and naming
+
+| #   | What changes | 1st-gen behavior | 2nd-gen behavior | Consumer migration path |
+| --- | ------------ | ---------------- | ---------------- | ----------------------- |
+| **B1** | `vertical` boolean → `orientation` property | `vertical` boolean attribute switches to column layout | `orientation="horizontal"` (default) or `orientation="vertical"`; explicit API aligned with React S2 and Figma | Replace `vertical` attribute with `orientation="vertical"`. Source: React S2 `orientation` prop. |
+| **B2** | Default size introduced | Accepts `'s'` \| `'m'` \| `'l'` \| `'xl'` (no default) | Accepts `'s'` \| `'m'` \| `'l'` \| `'xl'` with default `'m'` | Consumers without explicit `size` will now get `'m'` behavior. XL is supported; same 12px gap token as M/L. |
+
+#### Styling and visuals
+
+| #   | What changes | 1st-gen behavior | 2nd-gen behavior | Consumer migration path |
+| --- | ------------ | ---------------- | ---------------- | ----------------------- |
+| **B3** | Updated spacing tokens | Uses `--spectrum-spacing-300` (default), `--spectrum-spacing-200` (S) | Same tokens from spectrum-css `spectrum-two`; no visual change expected | No consumer action needed; visual refresh happens automatically. |
+
+#### Accessibility and behavior
+
+| #   | What changes | 1st-gen behavior | 2nd-gen behavior | Consumer migration path |
+| --- | ------------ | ---------------- | ---------------- | ----------------------- |
+| **B4** | Add `role="group"` on host | No role set on host | Host exposes `role="group"` via ElementInternals or explicit attribute | No consumer action; improvement is transparent. |
+| **B5** | Disabled propagation to children | Not supported | `disabled` attribute on host propagates `disabled` to each slotted `swc-button` | Consumers gain group-level disable; no breaking change. |
+
+### Additive — ships when ready, zero breakage for consumers already on 2nd-gen
+
+| #   | What is added | Notes |
+| --- | ------------- | ----- |
+| **A1** | `align` property (`"start"` \| `"center"` \| `"end"`) | Matches React S2 `align` prop. Maps to `justify-content`. Can ship after MVP. |
+| **A2** | Overflow behavior (auto-switch horizontal → vertical) | React S2 uses a `ResizeObserver` to detect overflow and switch orientation. Out of scope for MVP pending Q2. |
+| **A3** | `aria-label` / `aria-labelledby` attribute forwarding | Group naming for screen readers; recommended in accessibility analysis. Can be consumer-applied without API support. |
+
+---
+
+## 2nd-gen API decisions
+
+These are derived from the 1st-gen implementation, current deprecations, the Figma Desktop Button group spec, the React S2 implementation, and the rendering roadmap. Confirmed items are marked; open items are tracked in [Blockers and open questions](#blockers-and-open-questions).
+
+### Public API
+
+#### Properties / attributes (2nd-gen)
+
+| Property | Type | Default | Attribute | Notes |
+| -------- | ---- | ------- | --------- | ----- |
+| `orientation` | `'horizontal'` \| `'vertical'` | `'horizontal'` | `orientation` | **Confirmed.** Replaces `vertical` boolean. Aligns with React S2. |
+| `size` | `'s'` \| `'m'` \| `'l'` \| `'xl'` | `'m'` | `size` | **Confirmed.** React S2 includes XL. Size S uses 8px gap; M/L/XL share the same 12px gap token. 1st-gen had no default; 2nd-gen defaults to `'m'`. |
+| `disabled` | `boolean` | `false` | `disabled` | **Confirmed.** Aligns with React S2 `isDisabled`. Propagates to child buttons. |
+
+#### Visual matrix (2nd-gen)
+
+N/A. Button group is a layout container, not a visual component with fill/outline treatments. The buttons inside carry their own visual variants.
+
+Figma-confirmed presentation modes:
+
+- Horizontal orientation (default)
+- Vertical orientation
+- Size S, M, L, XL
+- 2+ buttons in group
+
+#### Slots (2nd-gen)
+
+| Slot | Content | Notes |
+| ------- | ------------------------- | -------------------------------------------- |
+| default | `swc-button` elements | **Confirmed.** Slotted children receive size and disabled propagation. |
+
+#### CSS custom properties (2nd-gen)
+
+No `--mod-*` properties will be exposed. New `--swc-*` component-level properties may be introduced where needed — these are additive and not breaking. See [Component Custom Property Exposure](../../../../CONTRIBUTOR-DOCS/02_style-guide/01_css/02_custom-properties.md#component-custom-property-exposure) for what to expose and how.
+
+Each exposed `--swc-*` property must be documented with a `@cssprop` JSDoc tag on the primary SWC component class. Storybook picks these up and surfaces them in the API docs panel automatically.
+
+Initial expectation for Button Group is a small reviewed set:
+
+| Property | Purpose | Notes |
+| -------- | ------- | ----- |
+| `--swc-button-group-gap` | Space between buttons | Allows consumer override of gap spacing |
+| `--swc-button-group-justify-content` | Alignment of buttons within the group | Only if `align` property is not shipped in MVP |
+
+### Behavioral semantics
+
+#### Size propagation
+
+When the `size` attribute changes or new children are slotted, the component iterates all assigned `swc-button` elements in the default slot and sets their `size` property to match. This matches 1st-gen behavior.
+
+#### Disabled propagation
+
+When `disabled` is set on the group host, all slotted `swc-button` elements receive `disabled`. When the attribute is removed, children are re-enabled. This mirrors React S2's `isDisabled` behavior.
+
+#### Orientation
+
+The `orientation` property controls CSS flex-direction (row vs column). The default is `"horizontal"`. Note: `aria-orientation` is **not** set on the host because it is only valid for roles that manage arrow-key navigation (e.g. `toolbar`, `listbox`), which button-group does not implement.
+
+### Accessibility semantics notes (2nd-gen)
+
+Sourced from the [accessibility migration analysis](./accessibility-migration-analysis.md):
+
+- **Host role:** `role="group"` (never `radiogroup` or `toolbar`)
+- **No `aria-orientation`:** This attribute is only valid for roles that manage arrow-key navigation direction (e.g. `toolbar`, `listbox`). Since button-group does not implement focus group behavior, `aria-orientation` is not set.
+- **Group name:** Optional `aria-label` / `aria-labelledby` when the group carries distinct meaning
+- **No roving tabindex:** Each button is a separate Tab stop; arrow-key navigation belongs on a parent toolbar/composite, not on button-group
+- **Focus:** Standard Tab/Shift+Tab through children in DOM order
+- **Not a toggle group:** No `aria-pressed` orchestration; that belongs on `swc-toggle-group`
+
+---
+
+## Architecture: core vs SWC split
+
+> The 1st-gen component is a **reference only** — 2nd-gen is built independently. Neither generation imports from the other.
+
+Follow the [Badge migration reference](../../02_workstreams/02_2nd-gen-component-migration/02_step-by-step/01_washing-machine-workflow.md#reference-badge-migration) as the concrete pattern for the core/SWC split.
+
+| Layer    | Path                                            | Contains                                                                                                                                                                                                                                          |
+| -------- | ----------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
+| **Core** | `2nd-gen/packages/core/components/button-group/` | `ButtonGroup.base.ts`, `ButtonGroup.types.ts`, validation (size/orientation normalization), disabled-propagation logic, ARIA attribute management (`role="group"`). No rendering. |
+| **SWC**  | `2nd-gen/packages/swc/components/button-group/`  | `ButtonGroup.ts`, `button-group.css`, element registration (`sp-button-group`), stories, tests, and the specific S2 rendering/styling. |
+
+Planned rendering shape:
+
+- Core owns API normalization (orientation, size, disabled propagation to children) and ARIA attribute management
+- SWC renders: a single `<slot>` element with `.swc-ButtonGroup` class for styling, flexbox layout driven by orientation and size
+
+---
+
+## Migration checklist
+
+### Preparation (this ticket)
+
+- [x] 1st-gen API surface documented
+- [x] Dependencies identified
+- [x] Breaking changes documented
+- [x] 2nd-gen API decisions drafted
+- [ ] Plan reviewed by at least one other engineer
+
+### Setup
+
+- [ ] Create `2nd-gen/packages/core/components/button-group/`
+- [ ] Create `2nd-gen/packages/swc/components/button-group/`
+- [ ] Wire exports in both `package.json` files
+- [ ] Check out `spectrum-css` at `spectrum-two` branch as sibling directory
+
+### API
+
+#### Naming and public surface
+
+- [ ] `ButtonGroup.types.ts`: define `ButtonGroupOrientation`, `ButtonGroupSize`, public property interfaces
+- [ ] `ButtonGroup.base.ts`: `orientation`, `size`, `disabled` properties with validation; size/disabled propagation to slotted children; `role="group"` management
+
+#### Alignment checks
+
+- [x] ~~Confirm XL size decision (Q1)~~ — **Resolved:** XL is supported. Same 12px gap token as M/L.
+- [ ] Confirm overflow behavior scope (Q2) before finalizing behavioral API
+
+### Styling
+
+> Follow the [CSS style guide](../../../../CONTRIBUTOR-DOCS/02_style-guide/01_css/) as the source of truth for all styling work. Key references: [migration steps](../../../../CONTRIBUTOR-DOCS/02_style-guide/01_css/04_spectrum-swc-migration.md), [custom properties](../../../../CONTRIBUTOR-DOCS/02_style-guide/01_css/02_custom-properties.md), [anti-patterns](../../../../CONTRIBUTOR-DOCS/02_style-guide/01_css/05_anti-patterns.md).
+
+- [ ] Add `.swc-ButtonGroup` to the internal semantic element in `render()`; keep styling off `:host`
+- [ ] Copy S2 source from `spectrum-css` `spectrum-two` branch `components/buttongroup/index.css` (not `/dist`) into `button-group.css` as baseline
+- [ ] Map `--spectrum-buttongroup-*` tokens to `:host` and orientation/size selectors
+
+#### Visual model and regressions
+
+- [ ] Verify size S spacing token (`--spectrum-spacing-200`) vs default (`--spectrum-spacing-300`)
+- [ ] Add `@cssprop` JSDoc tag for any exposed `--swc-*` properties
+- [ ] Pass stylelint (property order, `no-descending-specificity`, token validation)
+
+### Accessibility
+
+#### Naming and semantics
+
+- [ ] Host exposes `role="group"` (ElementInternals or explicit attribute)
+- [ ] No `aria-orientation` on host (only valid for roles managing arrow-key navigation)
+- [ ] `aria-label` / `aria-labelledby` passthrough supported
+- [ ] No `role="radiogroup"` or `role="toolbar"` on host
+- [ ] No `FocusgroupNavigationController` on button-group
+
+#### State verification
+
+- [ ] `disabled` propagation sets `disabled` on each slotted `swc-button`
+- [ ] Removing `disabled` from group re-enables children
+- [ ] Screen reader announces "group" landmark with name when provided
+
+### Testing
+
+- [ ] Port `1st-gen/packages/button-group/test/button-group.test.ts` coverage that still applies
+- [ ] Add Playwright `button-group.a11y.spec.ts` with `toMatchAriaSnapshot`
+
+#### Behavior
+
+- [ ] Size propagation: changing `size` on group updates all slotted buttons
+- [ ] Disabled propagation: setting `disabled` on group disables all children
+- [ ] Orientation: switching orientation changes flex-direction
+- [ ] Slotchange: newly slotted buttons receive current size and disabled state
+- [ ] Default size: group defaults to `size="m"` when no attribute set
+
+#### Visual regression
+
+- [ ] Add VRT coverage for horizontal and vertical orientations
+- [ ] Add VRT coverage for all size variants (S, M, L, XL)
+- [ ] Add VRT coverage for disabled group state
+
+### Documentation
+
+#### General
+
+- [ ] JSDoc on all public props, slots, and CSS custom properties
+- [ ] Storybook stories for: default, vertical, each size, disabled, alignment (if shipped)
+- [ ] Consumer migration guide documenting `vertical` → `orientation` change
+
+#### Breaking changes
+
+- [ ] Document `vertical` → `orientation="vertical"` migration path
+- [ ] Document default size change (1st-gen: none → 2nd-gen: `m`)
+
+### Review
+
+- [ ] `yarn lint:2nd-gen` passes (ESLint, Stylelint, Prettier)
+- [ ] Status table in workstream doc updated
+- [ ] PR created with description referencing Epic SWC-2071
+- [ ] Peer engineer sign-off
+
+---
+
+## Blockers and open questions
+
+### Design
+
+| #   | Item | Blocking? | Status | Owner |
+| --- | ---- | --------- | ------ | ----- |
+| **Q1** | ~~Should `size="xl"` be supported in 2nd-gen?~~ **Resolved:** Yes — React S2 also includes XL. Size S uses an 8px gap; M/L/XL all use the same 12px gap token. XL is included in the type definition and test matrix. | ~~Yes~~ Resolved | **Resolved** | @5t3ph |
+
+### Architecture and behavior
+
+| #   | Item | Blocking? | Status | Owner |
+| --- | ---- | --------- | ------ | ----- |
+| **Q2** | Should overflow behavior (auto-switch from horizontal to vertical when space is limited) be in MVP scope? React S2 implements this with a `ResizeObserver`. The Figma design spec does not mention it. **Reviewer feedback (@5t3ph):** Regular flex wrapping may be an acceptable starting point since button-group does not control arrow-key navigation. A container query or `ResizeObserver` could be added later for the all-at-once orientation switch. **Decision:** Defer from MVP; flex wrapping is a potential additive path. | No — additive | Deferred | Architecture reviewer |
+
+### Scope and prerequisites
+
+| #   | Item | Blocking? | Status | Owner |
+| --- | ---- | --------- | ------ | ----- |
+| **Q3** | Should `align` be part of MVP or additive? React S2 has `align` ("start"/"center"/"end") with "start" default. 1st-gen does not have it. **Recommendation:** Include in MVP; it is a simple CSS property mapping with no behavioral complexity. | No — recommended for MVP but not blocking | Open | Implementation |
+
+---
+
+## References
+
+- [Washing machine workflow](../../02_workstreams/02_2nd-gen-component-migration/02_step-by-step/01_washing-machine-workflow.md)
+- [2nd-gen migration status table](../../02_workstreams/02_2nd-gen-component-migration/01_status.md)
+- [Accessibility migration analysis](./accessibility-migration-analysis.md)
+- [Rendering and styling migration analysis](./rendering-and-styling-migration-analysis.md)
+- [CSS style guide — Component Custom Property Exposure](../../../../CONTRIBUTOR-DOCS/02_style-guide/01_css/02_custom-properties.md#component-custom-property-exposure)
+- [CSS style guide — Selector conventions](../../../../CONTRIBUTOR-DOCS/02_style-guide/01_css/02_custom-properties.md#selector-conventions)
+- [1st-gen source](../../../../1st-gen/packages/button-group/src/ButtonGroup.ts)
+- [1st-gen tests](../../../../1st-gen/packages/button-group/test/button-group.test.ts)
+- [1st-gen README](../../../../1st-gen/packages/button-group/README.md)
+- [React Spectrum S2 ButtonGroup](https://react-spectrum.adobe.com/ButtonGroup)
+- [Spectrum CSS — `spectrum-two` branch — `components/buttongroup/index.css`](https://github.com/adobe/spectrum-css/blob/spectrum-two/components/buttongroup/index.css)
+- [Spectrum CSS migration PR #2457](https://github.com/adobe/spectrum-css/pull/2457)
+- [Figma S2 / Web (Desktop scale) — Button group](https://www.figma.com/design/Mngz9H7WZLbrCvGQf3GnsY/S2---Web--Desktop-scale-?node-id=13663-6530)
+- [WAI-ARIA APG: Toolbar pattern](https://www.w3.org/WAI/ARIA/apg/patterns/toolbar/)
+- [WAI-ARIA APG: Keyboard navigation inside components](https://www.w3.org/WAI/ARIA/apg/practices/keyboard-interface/#keyboardnavigationinsidecomponents)
+- [Badge migration reference](../../02_workstreams/02_2nd-gen-component-migration/02_step-by-step/01_washing-machine-workflow.md#reference-badge-migration)
+- [Button migration plan](../button/migration-plan.md)
+- [Button accessibility migration analysis](../button/accessibility-migration-analysis.md)
+- Epic: SWC-2071 - Button group epic