Cloning a knowledge base previously copied only the storage path strings
(knowledge.FilePath and chunk.ImageInfo.URL), so the source and the clone
shared the same physical objects in the storage backend. Once the original
file and extracted images are deleted on source removal, the clone is left
with dangling references and its document and images become unreadable —
data loss that occurs even for same-store clones.
Add a CopyFile primitive to the FileService interface and implement it in
every backend: server-side CopyObject on the object stores
(s3/obs/cos/oss/tos/ks3/minio), io.Copy on local, and a no-op on dummy.
Destinations use the knowledge-owned layout and reuse the existing
path/object-key guards; a sentinel ErrCrossBackendCopy is returned when the
source scheme does not match the backend.
Use CopyFile to deep-copy the document file in cloneKnowledge and the
extracted images in CloneChunk and cloneFAQKnowledgeBase via a shared
cloneChunkImageInfo helper that deduplicates identical image URLs per clone
and rewrites them to the new objects. Copied objects are cleaned up
best-effort if a clone fails partway through. A clone-time preflight rejects
cloning into a target bound to a different storage backend when the tenant
pins providers via StorageEngineConfig.
Adds unit tests for local CopyFile (independent copy survives source
deletion, traversal rejection, cross-backend rejection), cloneChunkImageInfo
(empty/multi/dedup/parse-failure/OriginalURL handling), and the storage
provider preflight.
This commit introduces functionality to utilize the tenant's default storage provider when creating a Knowledge Base. It includes updates to the frontend to load the default provider from settings and apply it during Knowledge Base initialization. Additionally, the backend has been enhanced to ensure that the storage provider is set correctly based on tenant configuration, improving consistency across the application. Tests have been added to verify the correct application of the default storage provider in various scenarios.
Refactored the pinning mechanism for knowledge bases to be user-specific, allowing any user with read access to pin knowledge bases independently. This change includes the introduction of a new `user_kb_pins` table to manage pin states, replacing the previous tenant-wide pinning system. Updated relevant API endpoints and service logic to support this new functionality, ensuring that the UI reflects the user's personal pin status.
Additionally, adjusted the knowledge base listing to sort by user-specific pin status, enhancing the user experience by prioritizing pinned items.
Refs: #1303
Middleware
- RequireOwnershipOrRole now skips the creator lookup entirely when
EnableRBAC is off, eliminating a hidden per-request DB roundtrip in
the rollout window.
- New ErrResourceNotFound sentinel lets lookups signal "not visible to
this tenant"; the middleware passes the request through so handlers
can return a real 404 instead of a misleading 403.
- Transient lookup failures now surface as 503 (was 403) so monitoring
can tell denied-by-policy from cannot-verify-right-now.
- Cross-tenant superusers (CanAccessAllTenants) bypass tenant role gates,
restoring DELETE /tenants/:id and ResetAPIKey for org operators that
resolve to Admin in foreign tenants.
- Construction-time warning fires once when cfg is nil/incomplete, so a
wiring bug that disables enforcement globally is visible at boot.
Route coverage
- Add role guards to FAQ, KnowledgeTag, WikiPage, Skill, WebSearch,
WebSearchProvider, WeKnoraCloud, Session, Chat, and Message route
groups so the matrix actually matches the PR description.
Service layer
- KB and agent creators are no longer recorded as the synthetic
system-<tenantID> user used by the X-API-Key path; resources stay
tenant-owned. New types.IsSyntheticUserID helper centralises the
prefix check.
- KBCreatorLookup and AgentCreatorLookup re-check tenant scope so a
same-ID resource in another tenant cannot piggyback through the
ownership shortcut.
Docs
- CustomAgent.RunnableByViewer comment now matches enforcement: it only
blocks Viewer-driven agent-mode runs, not plain RAG/Wiki QA.
Tests
- New cases for the 503/404 paths, lookup-skip behaviour, cross-tenant
superuser bypass, the lookup helpers (not-found, cross-tenant,
built-in agent, missing tenant context), and IsSyntheticUserID.
Build on PR 1's tenant_members schema by enforcing the role matrix on
every authenticated route and at agent run time. Enforcement is gated
behind cfg.Tenant.EnableRBAC so the change ships dormant — the same
code paths log the would-be rejection during the rollout window and
start blocking once operators flip the flag.
Middleware (internal/middleware/rbac.go):
- RequireRole(min, cfg): role-only gate using TenantRole.HasPermission.
- RequireOwnershipOrRole(min, lookup, cfg): allows the original creator
through even when their role is below min, otherwise falls back to
the role check. Lookup errors fail closed; an empty creator_id is
treated as tenant-owned and requires the role.
- Both honour cfg.Tenant.EnableRBAC for the rollout window.
Creator lookups (internal/handler/rbac_lookups.go):
- KBCreatorLookup resolves :id -> KnowledgeBase.CreatorID.
- AgentCreatorLookup resolves :id -> CustomAgent.CreatedBy; built-in
agents (IsBuiltin=true) return ("", nil) so they remain Admin+ only.
- Compile-time guards keep the methods aligned with CreatorLookup.
Route guards (internal/router/rbac.go + router.go):
- rbacGuards bundles the matrix into Viewer/Contributor/Admin/Owner
helpers plus OwnedKBOrAdmin / OwnedAgentOrAdmin. Each Register*
function takes *rbacGuards so route lines remain readable.
- KB / Agent / Knowledge / Chunk / Tenant / Model / MCPService /
VectorStore / DataSource / IMChannel routes annotated per the PR 1
design doc matrix. Tenant-wide infra (models, vector stores, MCP,
data sources, IM channels) reads as Viewer+ and writes as Admin+;
per-resource mutations on KB / Agent route through the
ownership-or-Admin guard.
Resource ownership (services):
- CreateKnowledgeBase / CopyKnowledgeBase populate CreatorID from the
authenticated user, so the OwnedKBOrAdmin guard has a creator to
match.
- CreateAgent / CopyAgent populate CreatedBy similarly. Built-in
agents stay tenant-owned.
Agent run-time gate (internal/handler/session/qa.go):
- AgentQA refuses to launch the agent engine for Viewers when the
target agent has RunnableByViewer=false. Same EnableRBAC gating as
the middleware so it's a no-op until enforcement is turned on.
Tests:
- 12 unit tests cover RequireRole / RequireOwnershipOrRole, including
the fail-open and fail-closed branches and the lookup-error path.
Wires KnowledgeBase.VectorStoreID and the ownership-aware retrieve factory
into the user-facing knowledge-base lifecycle:
- POST /knowledge-bases validates the requested vector_store_id against
the caller's tenant scope and the engine registry. New error codes
ErrVectorStoreBindingInvalid (2200) and ErrVectorStoreUnavailable (2201)
distinguish the typed branches without echoing UUIDs to the client.
- GET / POST / PUT / PUT-pin responses embed the bound store's display
metadata (name, source, engine_type, status) without exposing any
connection credentials. Cross-tenant shared KBs receive a suppressed
payload (vector_store_id stripped, source="shared") so operator-chosen
store names cannot be enumerated across tenants.
- POST /knowledge-bases/copy synchronously rejects clones whose target
has a different embedding model or vector store, before the async
clone task is enqueued. The async clone worker re-applies the same
checks for defense in depth.
- DELETE /vector-stores/:id refuses to remove a store with bound KBs,
inside a transaction that row-locks the store on PostgreSQL and
serializes via WAL on SQLite. unregister-from-registry is wrapped in
defer/recover so a panic surfaces as a structured warning instead of
silently leaking a stale engine.
- vector_store_id is immutable after creation. The GORM <-:create tag
blocks every ORM update path; the service-layer DTO omits the field
entirely; a reflection-based regression test catches any future
maintainer who adds it back to either layer.
- Empty-string vector_store_id is normalized to nil at both the create
path and inside SharesStoreWith, so rows persisted by callers that
did not run Normalize first cannot trip false same-store comparisons.
Part of #993. Depends on #994 and #1310.
Extracts the 25 repeated NewCompositeRetrieveEngine call sites across
seven services into two factory functions with tenant-ownership
verification: CreateRetrieveEngineForKB (synchronous) and
CreateRetrieveEngineFromPayload (async task handlers). Promotes
GetByStoreID from concrete-only to interfaces.RetrieveEngineRegistry.
Extends KBDeletePayload / IndexDeletePayload with an omitempty
VectorStoreID snapshot.
Design highlights
- Factory verifies tenant ownership of the resolved store
(defense-in-depth) so a gap in PR3 validation or a tampered Asynq
payload cannot cross tenants. Cross-tenant attempts return
ErrVectorStoreForbidden with a structured log entry.
- Sentinel errors (ErrTenantInfoMissing, ErrVectorStoreNotFound,
ErrVectorStoreForbidden) let async handlers classify non-retryable
failures as asynq.SkipRetry.
- nil and empty-string pointers for vectorStoreID normalize to
"unbound" so callers never send an empty UUID to GetByStoreID.
- resolveBoundEngine constructs engineInfos directly (with
slices.Clone of Support()) instead of going through
NewCompositeRetrieveEngine. The latter only reads from the
byEngineType map and cannot reach DB stores in byStoreID -- multiple
stores can share the same engine type. Unbound fallbacks still reuse
NewCompositeRetrieveEngine so the tenant effective-engines path is
byte-for-byte unchanged.
- DeleteKnowledgeBase now reads the KB before soft-delete so the
enqueued KBDeletePayload carries a VectorStoreID snapshot; once the
row is soft-deleted GORM's default scope hides it. Cost: +1 SELECT
per KB-delete request (a rare admin operation).
- enqueueIndexDeleteTask gains a vectorStoreID *string parameter that
the single caller (tag.go) populates from the owning KB. The worker
(ProcessIndexDelete) validates ownership via the factory.
- cleanupKnowledgeResources loads the KB so bound-store cleanup routes
correctly. If the load fails it warns and falls back to tenant
effective engines; orphan vectors become observable in logs instead
of disappearing silently.
- DeleteKnowledges (batch) stays on the tenant effective-engines path
-- batches can span stores and multi-store fan-out is PR4 scope.
Noted inline.
Merge safety
All knowledge bases have VectorStoreID = NULL at merge time (introduced
nullable in PR1, Tencent/WeKnora#994). Every factory call falls back to
NewCompositeRetrieveEngine(registry, tenantInfo.GetEffectiveEngines()),
which is the existing code path for these KBs. Async payloads from
before this change decode to VectorStoreID = nil (omitempty) and take
the same fallback.
Testing
- go build ./...
- go vet ./...
- go test -race -count=1 ./internal/application/service/retriever/...
covers unbound (nil/empty), bound, cross-tenant, unregistered store,
ownership infra error, legacy payload shapes (missing field/null/
empty string/nil), tampered payload, and parallel invocation.
- grep -r NewCompositeRetrieveEngine internal/application/service
returns zero results outside factory.go/composite.go.
Refs: Part of Tencent/WeKnora#993. Depends on Tencent/WeKnora#994.
Previously the Langfuse integration only traced in-process HTTP requests
(chat / search / eval), so file uploads and every downstream asynq task
(document parse, chunk embedding, OCR/VLM, summary / question gen, wiki
ingest, datasource sync, etc.) produced either disconnected shallow
traces or no observation at all.
This change threads one trace end-to-end:
- tracer: add SPAN observation type and StartSpan; add ResumeTrace so a
worker can attach to an upstream trace without emitting a duplicate
trace-create; StartGeneration now auto-picks parentObservationId from
ctx so nested trace -> span -> generation trees render correctly.
- types.TracingContext + LangfuseTracingCarrier: embed on all 17 asynq
payloads so trace_id / parent_obs_id / user_id / session_id serialise
into every job.
- langfuse.InjectTracing: injected at 28 enqueue sites before json.Marshal
so the HTTP-layer trace survives the Redis hop.
- langfuse.AsynqMiddleware: mux.Use hook that peeks the payload, either
resumes the upstream trace or opens a standalone asynq.<type> trace
for scheduled jobs, and wraps the handler in a SPAN with task metadata
(id / queue / retry / payload_bytes) plus ERROR level on failure.
- GinMiddleware.shouldTrace: whitelist ingestion / knowledge-mutation /
FAQ / wiki / datasource endpoints so the root trace actually starts.
- Tests: tracer_test.go covers span nesting, error status, and
ResumeTrace no-trace-create guarantee; asynq_test.go covers
InjectTracing round-trip, middleware resume path, and standalone
trace fallback.
- Docs: docs/Langfuse\u96c6\u6210.md now lists the covered task types
and documents the cross-process propagation model.
No behavioural change when Langfuse is disabled (all new code paths are
no-ops and carriers serialise to empty strings with omitempty).
- Updated the knowledge base service to ensure WikiConfig is created when wiki indexing is enabled, enhancing backward compatibility.
- Removed legacy syncing of WikiConfig.Enabled to IndexingStrategy.WikiEnabled, streamlining the logic for wiki enablement.
- Introduced a custom retry delay function for asynq tasks to handle wiki ingest lock conflicts more effectively, improving task management.
- Cleaned up the container file by removing unnecessary whitespace, contributing to better code readability.
- Introduced multiple new documentation files, including a complete documentation index, quick reference guides, and comprehensive analyses of the knowledge base and wiki settings.
- The new files provide detailed insights into the architecture, data models, API endpoints, and implementation strategies for the knowledge base and wiki functionalities.
- Enhanced navigation and usability for developers and team members by summarizing key components, configurations, and data flows related to the knowledge base system.
These additions significantly improve the clarity and accessibility of documentation, supporting better onboarding and reference for current and future team members.
Implemented three critical fixes to enable wiki_config persistence during
KB creation and updates:
1. Add WikiConfig field to KnowledgeBaseConfig struct
- File: internal/types/knowledgebase.go
- Enables JSON unmarshaling of wiki_config from update requests
- Previously the field was silently dropped during deserialization
2. Update UpdateKnowledgeBase service to persist wiki_config
- File: internal/application/service/knowledgebase.go
- Added logic to apply wiki_config changes when config parameter is provided
- Mirrors existing logic for FAQConfig persistence
3. Update frontend TypeScript types for IDE completion
- File: frontend/src/api/knowledge-base/index.ts
- Added WikiConfig type to createKnowledgeBase function signature
- Added structured WikiConfig type to updateKnowledgeBase config parameter
- Enables TypeScript IDE autocomplete and type checking
Flow:
- Frontend: updateKnowledgeBase({name, description, config: {wiki_config}})
- Handler: Parses into UpdateKnowledgeBaseRequest via KnowledgeBaseConfig
- Service: Applies wiki_config to KB entity via UpdateKnowledgeBase
- Database: Persists wiki_config JSONB field to postgres
Root cause analysis:
Previously, the KnowledgeBaseConfig struct was missing the WikiConfig field,
causing JSON unmarshaling to silently drop any wiki_config data sent in
PUT requests. KB creation worked because it used the full KnowledgeBase struct.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Previously, only the original uploaded file was deleted via knowledge.FilePath.
Images extracted by the builtin parser (stored as individual S3/MinIO/local files
via ImageResolver) were never cleaned up, causing orphan files to accumulate.
- Add ListImageInfoByKnowledgeIDs repository method (no chunk_type filter)
- Add collectImageURLs utility with URL deduplication and JSON parse logging
- Add deleteExtractedImages helper (standalone, best-effort with error logging)
- Fix DeleteKnowledge: collect image URLs before errgroup, delete in file goroutine
- Fix DeleteKnowledgeList: bulk collect with KB-level fileSvc mapping
- Fix cleanupKnowledgeResources: collect before chunk deletion, delete after
- Fix ProcessKBDelete: collect before chunk deletion for KB-wide cleanup
- Added blur handling for the textarea in the Input-field component to prevent errors when navigating away from the component.
- Improved the sanitization process in the AgentStreamDisplay component to preserve specific tags during markdown processing, ensuring accurate content display.
- Introduced new methods for handling FAQ-specific post-processing in the knowledge base service, optimizing retrieval and filtering of search results.
These changes enhance user experience by improving input handling and content rendering in the chat interface.
- Introduced a new method to resolve embedding model IDs to their actual identity keys (name + endpoint), enabling optimal grouping of knowledge bases across different tenants.
- Updated the concurrent search functionality to utilize the resolved model keys, improving the efficiency of query embedding computations.
- Refactored search target grouping to reduce redundant API calls and enhance performance during hybrid searches.
These changes significantly improve the knowledge search process by ensuring that embeddings are computed efficiently and reused across multiple knowledge bases sharing the same underlying model.
- Enhanced the concurrent search functionality to group search targets by their embedding model, allowing for a single computation of query embeddings per model.
- Implemented batch fetching of knowledge base records to improve efficiency and reduce redundant API calls.
- Updated the HybridSearch method to support multiple knowledge base IDs, enabling combined retrieval for full-KB targets and improving overall search performance.
- Added a new GetQueryEmbedding method to compute embeddings for queries, facilitating reuse across multiple knowledge bases sharing the same model.
These changes significantly enhance the performance and efficiency of the knowledge search process, reducing API calls and improving response times.
- Added support for updating the description field in knowledge records, improving the detail and context of knowledge entries.
- Refactored knowledge base update logic to ensure configuration updates are only applied when provided, enhancing robustness and preventing unnecessary overwrites.
- Modified the request structure to make the configuration field optional, allowing for more flexible updates.
These changes improve the knowledge management system by allowing for more comprehensive updates and better handling of configuration data.
- Updated configuration to improve handling of multimodal queries, including clearer guidelines for when to use [NO_SEARCH] in responses.
- Enhanced the user interface to include dedicated sections for multimodal configuration, allowing users to manage image uploads and related settings more effectively.
- Added localization support for new multimodal features in both English and Chinese, improving accessibility for a broader audience.
- Implemented backend changes to support image analysis and extraction of OCR text, enriching the interaction experience for users.
These enhancements significantly improve the application's capability to process and respond to multimodal queries, fostering a more interactive and user-friendly environment.
- Introduced a new API endpoint to toggle the pin status of knowledge bases, allowing users to pin important entries to the top of the list.
- Updated the frontend to include UI elements for pinning and unpinning knowledge bases, with corresponding success and error messages.
- Enhanced localization support by adding translations for pinning actions in English, Korean, Russian, and Chinese.
- Modified the database schema to include `is_pinned` and `pinned_at` fields for knowledge bases, enabling persistent pinning status.
These changes improve the organization and accessibility of knowledge bases, enhancing user experience by allowing quick access to prioritized entries.
- Added support for parent-child chunking in the knowledge base, allowing for a two-level chunking strategy that improves context retrieval.
- Introduced new configuration options for enabling parent-child chunking, including parent and child chunk sizes.
- Updated relevant components and services to handle parent chunk data, ensuring proper linking and retrieval of child chunks.
- Enhanced user interface elements to reflect the new chunking options and provide better user guidance.
These changes significantly improve the knowledge extraction process by providing richer context through hierarchical chunking.
- Added a new `StorageProviderConfig` struct to the `KnowledgeBase` for improved storage provider management, separating provider selection from storage credentials.
- Updated the `UnmarshalJSON` method to auto-populate `StorageProviderConfig` from the legacy `StorageConfig` for backward compatibility.
- Refactored various service methods to utilize the new storage provider configuration, ensuring a smooth transition from the legacy system.
- Implemented database migrations to add the `storage_provider_config` column and migrate existing data, maintaining compatibility with historical knowledge bases.
This update enhances the clarity and flexibility of storage configurations while ensuring compatibility with existing data structures.
- Introduced a loading state (`loadingChunks`) to manage document chunk loading more effectively.
- Updated the scroll handling logic to prevent multiple requests while loading chunks.
- Adjusted the pagination logic to ensure correct page increments based on the total document count.
This update improves the user experience by ensuring smoother document loading and better state management during scrolling interactions.
- Added a new `.env.lite.example` file for the Lite version, providing a minimal configuration template.
- Updated `.env.example` to remove deprecated variables and include new Docreader settings.
- Enhanced Docker configurations to support the Lite version, including a new Dockerfile for the Docreader service.
- Introduced a Makefile target for building and running the Lite version, along with packaging capabilities.
- Created GitHub workflows for building and releasing Lite binaries, including Homebrew formula support.
- Implemented a new service file for managing the Lite version as a system service.
This update enables a streamlined, single-binary deployment of WeKnora, reducing external dependencies and simplifying setup.
- Updated the AgentSelector component to improve agent selection logic, ensuring accurate representation of selected agents.
- Introduced new AgentShareSettings component for managing agent sharing with organizations, including UI for selecting organizations and displaying shared agents.
- Enhanced API interactions for sharing agents, including new methods for listing and managing agent shares.
- Improved localization support for agent sharing features across multiple languages.
- Updated various components to reflect changes in agent capabilities and sharing status, enhancing user experience and clarity.
This update strengthens the agent management features, providing users with better tools for sharing and selecting agents within organizations.
- Introduced a new API for organization management, including creation, updating, and deletion of organizations.
- Implemented organization sharing functionality for knowledge bases, allowing users to share knowledge bases with specific organizations and set permissions.
- Added UI components for organization selection and sharing dialogs.
- Enhanced existing components to support organization-related features, including shared knowledge base handling and organization role management.
This update enhances collaboration capabilities within the application by allowing users to manage and share knowledge bases across different organizations.
- Added GetKnowledgeBaseByIDAndTenant method to enforce tenant isolation when retrieving knowledge bases by ID.
- Updated CopyKnowledgeBase method to use tenant-scoped retrieval, preventing cross-tenant cloning.
- Enhanced error handling in the KnowledgeBaseHandler to validate tenant ownership for source and target knowledge bases during copy operations.
- Updated the `uploadKnowledgeFile` function to accept an optional progress callback, enabling real-time upload progress tracking.
- Refactored the document upload handling in the menu component to support multiple file uploads with individual progress events.
- Removed deprecated document processing state management from the KnowledgeBase view, streamlining the upload process.
- Improved user feedback during file uploads by dispatching events for upload start, progress, and completion.
- Added support for tracking the status of FAQ import tasks, including progress indicators for ongoing imports.
- Introduced new localization strings for processing tasks and batch operations in multiple languages.
- Updated the FAQ entry manager to display import progress and improved user feedback during the import process.
- Enhanced the KnowledgeBase component to reflect the processing state of knowledge items, improving user experience during document uploads.
- Implemented batch deletion functionality for chunks, streamlining the management of knowledge base content.
- Added a new menu item for searching FAQs directly from the menu, improving user accessibility.
- Implemented batch action options for selected FAQs, allowing users to perform bulk operations such as enabling, disabling, and deleting entries.
- Updated localization strings to support new features and improve user experience across multiple languages.
- Enhanced the handling of FAQ selection changes to dynamically update the UI based on user interactions.
- Introduced new localization strings for document count, FAQ entries, and chunk count in English, Russian, and Chinese.
- Updated the KnowledgeBase and KnowledgeBaseList components to display knowledge and chunk counts.
- Implemented backend functions to count knowledge items and chunks associated with each knowledge base, improving data management and user insights.
- Replaced `vlm_model_id` with a structured `vlm_config` object in knowledge base configurations, including `enabled` flag and `model_id`.
- Updated API documentation to reflect changes in VLM configuration structure.
- Enhanced frontend interfaces to accommodate new VLM configuration format.
- Improved localization for new features related to knowledge graph and multimodal capabilities.
- Updated agent configuration to support separate system prompts for web search enabled and disabled states.
- Removed deprecated agent configuration parameters to streamline settings management.
- Enhanced UI components in AgentSettings.vue to allow configuration of custom prompts based on web search status.
- Improved localization in English, Russian, and Chinese for new prompt settings and UI elements.
- Refactored related API and service logic to accommodate changes in agent configuration structure.
- Removed outdated DEVELOPMENT.md, consolidating development instructions into relevant documentation.
- Updated conversation configuration to include new parameters such as max rounds, embedding thresholds, and rewrite prompts.
- Enhanced UI components to support new conversation settings, including AgentSettings.vue and related views.
- Improved localization in English, Russian, and Chinese for new conversation configuration fields and UI elements.
- Implemented logic to apply tenant-specific conversation settings, ensuring defaults are respected.
- Introduced a new boolean field for MinIO status in the system info API response.
- Updated localization files in English, Russian, and Chinese to include warnings and instructions related to MinIO and graph database configurations.
- Enhanced the KBAdvancedSettings component to display alerts and disable options based on the status of MinIO and graph database.
- Implemented logic to check system status on component mount and adjust settings accordingly.
- Added support for creating and managing FAQ knowledge bases, including new API endpoints for listing, upserting, updating, and deleting FAQ entries.
- Enhanced the frontend to allow users to create FAQ knowledge bases and manage FAQ entries with a dedicated interface.
- Introduced new types and configurations for FAQ handling in the backend, ensuring proper indexing and retrieval of FAQ entries.
- Updated localization files to include new strings related to FAQ management in multiple languages.
- Refactored existing components to accommodate the new FAQ features, improving user experience and functionality.
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