[Flyout System] Scoped history

[tsullivan]

Summary

Closes elastic/kibana#250889

Makes flyout histories scoped by historyKey.

This branch introduces a new optional historyKey?: symbol prop to EuiFlyout and threads it through the entire flyout manager stack. The purpose is to scope Back-button navigation and history to a specific group of flyouts, preventing different product domains from mixing their flyout histories.

API Changes

component / parent	prop / child	change	description
EuiFlyout	historyKey	Added	Optional symbol to scope flyout history. Flyouts sharing the same Symbol reference share Back-button navigation and history entries.
FlyoutManagerStore	addFlyout	Updated	Added optional historyKey?: symbol parameter (position 5, between size and iconType). Callers passing iconType/minWidth positionally must update their call sites.
FlyoutSession	historyKey	Added	New required field (symbol) on the FlyoutSession type; assigned automatically — no consumer action needed unless constructing sessions manually.

Screenshots

This PR doesn't add visual changes. It's a user-interaction change for an EUI flyout's "Back" button to show up only in expected scenarios.

Impact Assessment

• 🔴 Breaking changes — What will break? How many usages in Kibana/Cloud UI are impacted?

• FlyoutManagerApi.addFlyout is a method signature change, not a new prop
  • historyKey is optional and inserted before iconType, it is technically a breaking positional change for any callers passing iconType or minWidth. No known usages / use cases for this.
  • One alternative that wasn't pursued was to change the addFlyout signature to accept an options object rather than positional arguments.

• [ ] 💅 Visual changes — May impact style overrides; could require visual testing. Explain and estimate impact.
• [ ] 🧪 Test impact — May break functional or snapshot tests (e.g., HTML structure, class names, default values).
• [ ] 🔧 Hard to integrate — If integration is complex, stage commits in Kibana/Cloud UI branches for cherry-picking and link to them below.

Impact level: 🟢 None. There are no zknown external consumers of FlyoutManagerApi. The updated methods are meant to be called from internal hooks.

Release Readiness

• Documentation: {link to docs page}
• [ ] Figma: {link to Figma or issue}
• [ ] Migration guide: {steps or link, for breaking/visual changes or deprecations}
• [ ] Adoption plan (new features): {link to issue/doc or outline who will integrate this and where}

QA instructions for reviewer

Checklist before marking Ready for Review

• Filled out all sections above
• [ ] QA: Tested light/dark modes, high contrast, mobile, Chrome/Safari/Edge/Firefox, keyboard-only, screen reader
• QA: Tested in CodeSandbox and Kibana
• QA: Tested docs changes
• Tests: Added/updated Jest, Cypress, and VRT
• Changelog: Added changelog entry
• Breaking changes: Added breaking change label (if applicable)

Reviewer checklist

• Approved Impact Assessment — Acceptable to merge given the consumer impact.
• Approved Release Readiness — Docs, Figma, and migration info are sufficient to ship.

[github-actions]

This PR contains breaking changes. The opener of this pull request is asked to perform the following due diligence steps below, to assist EUI in our next Kibana upgrade:

• If this PR contains prop/API changes:
  • Search through Kibana for <EuiComponent usages (example search)
  • In the PR description or in a PR comment, include a count or list with the number of component usages in Kibana that will need to be updated (if that amount is "none", include that information as well)
• If this PR contains CSS changes:
  • [ ] Search through Kibana for the changed EUI selectors, e.g. .euiComponent (example search)
  • [ ] In the PR description or in a PR comment, include a count or list with the number of custom CSS overrides in Kibana that will need to be updated (if that amount is "none", include that information as well)
• 🔍 Tip: When searching through Kibana, consider excluding **/target, **/*.snap, **/*.storyshot files to reduce noise and only look at source code usages
• ⚠️ For extremely risky changes, the EUI team should potentially consider the following precautions:
  • Using a pre-release release candidate to test Kibana CI ahead of time
  • Using kibana-a-la-carte for manual QA, and to give other Kibana teams a staging server to quickly test against

Log | Bot Usage

[tsullivan]

If this PR contains prop/API changes:

• In the PR description or in a PR comment, include a count or list with the number of component usages in Kibana that will need to be updated (if that amount is "none", include that information as well)

None.

[Copilot]

Pull request overview

Scopes flyout session history/back-navigation so that only flyouts belonging to the same historyKey group participate in the Back button + history popover, preventing unrelated product areas from mixing histories.

Changes:

• Added optional historyKey?: symbol to EuiFlyout and threaded it through the managed flyout stack (addFlyout action/store/API + session state).
• Updated flyout manager history computation and navigation/close behavior to operate within a history group (including ACTION_CLOSE_ALL and group-local goBack/goToFlyout behavior).
• Updated tests, stories, docs, and changelog to reflect the new history scoping behavior.

Reviewed changes

Copilot reviewed 17 out of 17 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
packages/website/docs/components/containers/flyout/_session_management.mdx	Documents historyKey behavior and provides examples for scoped history groups.
packages/eui/src/components/flyout/manager/types.ts	Extends FlyoutSession with historyKey and updates addFlyout API signature.
packages/eui/src/components/flyout/manager/store.ts	Filters history items to only include sessions in the same historyKey group; updates store addFlyout signature.
packages/eui/src/components/flyout/manager/store.test.ts	Updates/adds tests validating scoped history behavior across multiple groups.
packages/eui/src/components/flyout/manager/reducer.ts	Implements historyKey assignment and group-scoped behavior for close/back/navigate actions.
packages/eui/src/components/flyout/manager/reducer.test.ts	Updates/adds reducer tests for multi-group close/back/navigation behavior.
packages/eui/src/components/flyout/manager/layout_mode.test.tsx	Updates mock session construction to include historyKey.
packages/eui/src/components/flyout/manager/flyout_sessions.stories.tsx	Updates Storybook demos to illustrate independent history groups and shared keys.
packages/eui/src/components/flyout/manager/flyout_managed.tsx	Threads historyKey into addFlyout registration for main flyouts only.
packages/eui/src/components/flyout/manager/activity_stage.test.tsx	Updates mock state sessions to include historyKey.
packages/eui/src/components/flyout/manager/actions.ts	Adds historyKey to addFlyout action payload/signature and docs.
packages/eui/src/components/flyout/manager/actions.test.ts	Updates action tests and adds coverage for historyKey in payload.
packages/eui/src/components/flyout/manager/mocks/index.ts	Updates test session factory to always provide a historyKey.
packages/eui/src/components/flyout/manager/README.md	Adds developer-facing explanation of historyKey scoping semantics.
packages/eui/src/components/flyout/flyout.tsx	Adds public historyKey?: symbol prop and passes it into managed flyout variants.
packages/eui/src/components/flyout/flyout.test.tsx	Adds test ensuring historyKey is accepted on session="start" flyouts.
packages/eui/changelogs/upcoming/9413.md	Changelog entry describing the new historyKey feature and close behavior change.

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[tkajtoch]

Code changes look great and work as expected. Thank you for updating the sessions story to nicely demo this new functionality! It made validating the changes very easy 💯

[elasticmachine]

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[elasticmachine]

💚 Build Succeeded

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• Commit: 179e9f6

History

• 💔 Build #6099 failed d459ef3
• 💚 Build #6078 succeeded 0c2402d
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