Implement Search RHS popout, clean up and rework parts of search RHS

[Combs7th]

@claude, Let's update the Mattermost Product Documentation to reflect the end user product experience for RHS popouts from Mattermost v11.6.0 onward, starting from engineering PR mattermost/mattermost#35499.

Context:

• The immediate engineering source of truth for this effort is PR #35499: [MM-65630] Implement Search RHS popout, clean up and rework parts of search RHS mattermost#35499
• The developer confirmed that docs currently do not appear to cover popouts holistically, and suggested that instead of documenting this PR in isolation, we should likely document popouts more broadly in one coherent place, covering examples like Channels, Search RHS, Agents/other plugin RHS, and Threads.
• This means the task is: use PR #35499 as the starting point, but first assess whether the best documentation outcome is a small PR-specific update, or a broader holistic update to existing end-user docs about popouts.

Before proposing any changes:

• First, assess whether a docs update is necessary at all based on explicit PR evidence.
• Then determine whether this should be documented:
• as a narrow update for Search RHS popouts only, or
• as a broader end-user documentation update for popout behavior in general.
• Identify the existing end-user documentation page(s) that are the best fit for this content.
• Review those page(s) carefully for writing style, tone, structure, heading patterns, formatting, and level of detail.

Grounding requirements:

• PR #35499 explicitly includes:
  • a popout button added to the search results header,
  • opening the current search view in a popout window,
  • preserving the search query and other parameters,
  • reply/thread navigation inside the popout,
  • a back button to return to results within the popout flow,
  • Jump opening the channel in the main window,

When drafting updates:

• Focus on the user-visible capability gain, not implementation details.
• Do not document internal refactors, hooks, routing internals, typings, or architecture changes.
• Do not create documentation sprawl.
• Prefer the smallest clean documentation update that gives users a clear mental model of what popouts are and where they apply.
• If a holistic popouts update is the better choice, keep the PR-scoped content tightly limited to what PR #35499 actually adds or confirms.
• Match existing Mattermost docs voice and structure exactly.
• Do not add brand new sections unless the current docs structure clearly needs one.
• Do not modify changelogs, important upgrade notes, version archive pages, removed/deprecated-feature pages, or unsupported legacy release docs.

[claude]

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[claude]

Claude finished @Combs7th's task in 3s —— View job • claude/issue-8852-20260407-2037 • Create PR ➔

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Analysis and implementation complete

• Gather context and understand the request
• Read CLAUDE.md for repo-specific instructions (none found)
• Fetch engineering PR #35499 for feature details (grounded from issue body)
• Explore existing docs structure for search/popout documentation
• Assess scope: narrow vs. holistic update
• Identify best-fit pages and review their style/structure
• Draft and implement documentation updates
• Commit and push changes

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Scope decision

• search-for-messages.rst covers search with no mention of popouts — best fit for this update
• organize-conversations.rst already has a brief mention of opening threads in new windows (v11.2) — no change needed
• No holistic "popouts" page exists, and adding one would create sprawl given the existing per-feature structure

Verdict: Narrow update to search-for-messages.rst is the right call. The feature is specific to search, the existing thread popout already has its own mention, and the issue instructs to avoid unnecessary sprawl.

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Change made

Added a new Open search results in a popout window subsection to source/end-user-guide/collaborate/search-for-messages.rst, covering all six user-visible behaviors from PR #35499:

• Opening search results in a popout window (v11.6)
• Popout button in the search results header (|new-window-icon| icon, consistent with thread popout docs)
• Search query and parameter preservation
• Thread/reply navigation within the popout
• Back button to return to search results
• Jump opening the source channel in the main window

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