feat(frontend): enable React StrictMode at root by rusackas · Pull Request #39893 · apache/superset

rusackas · 2026-05-05T16:48:46Z

SUMMARY

First foundational step for #39890 (React 18 concurrent-feature adoption).

Wraps the three React 18 root mounts in <StrictMode>:

superset-frontend/src/views/index.tsx (main app)
superset-frontend/src/views/menu.tsx (backend-rendered views' menu)
superset-frontend/src/embedded/index.tsx (embedded SDK)

Why

Per the React 18 docs, StrictMode's dev-mode double-invocation surfaces effect-cleanup and non-idempotent-render bugs that concurrent rendering will eventually expose at runtime. Turning it on now lets us catch those deliberately during local dev rather than have them appear later as "weird remount" or stale-state regressions.

Scope notes

Dev-only. StrictMode is a no-op in production React builds; this PR has zero production impact.
Test suite unaffected. The custom RTL render wrapper at spec/helpers/testing-library.tsx does not enable StrictMode, so existing tests behave identically.
No effect-cleanup audit in this PR. The tracking issue's own guidance is "Expect a follow-up wave of small fixes once it's on. Plan for a cleanup pass; don't merge alongside other work." Any double-mount issues that surface during local dev should be triaged as discrete follow-ups against TODO: Adopt React 18 concurrent features now that the upgrade has landed #39890.

BEFORE/AFTER SCREENSHOTS OR ANIMATED GIF

N/A — no UI change. Dev-mode console may now show second-invocation warnings for components with cleanup bugs; those are pre-existing latent issues to be fixed in follow-ups.

TESTING INSTRUCTIONS

npm run dev from superset-frontend/.
Load any page (dashboard, explore, SQL Lab, embedded) — verify the app renders normally.
Open the browser console; existing functionality should work. Expect possible new warnings from React about effects/refs in components that aren't yet idempotent — these are not regressions from this PR but are pre-existing issues StrictMode is now surfacing.
Run npm run build to confirm production builds still succeed (StrictMode is stripped in prod).

ADDITIONAL INFORMATION

Has associated issue: TODO: Adopt React 18 concurrent features now that the upgrade has landed #39890
Required feature flags:
Changes UI
Includes DB Migration
Introduces new feature or API
Removes existing feature or API

Wrap the three React 18 root mounts (views/index, views/menu, embedded) in <StrictMode>. Refs #39890. StrictMode is dev-only — production builds are unchanged. The RTL test wrapper does not enable StrictMode, so the existing test suite is unaffected. Any double-invocation/cleanup issues that surface during local dev work should be tracked as follow-up items. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

bito-code-review · 2026-05-05T16:48:56Z

Code Review Agent Run #541f49

Actionable Suggestions - 0

Review Details

Files reviewed - 3 · Commit Range: 893a780..893a780
- superset-frontend/src/embedded/index.tsx
- superset-frontend/src/views/index.tsx
- superset-frontend/src/views/menu.tsx
Files skipped - 0
Tools
- Whispers (Secret Scanner) - ✔︎ Successful
- Detect-secrets (Secret Scanner) - ✔︎ Successful

Bito Usage Guide

Commands

Type the following command in the pull request comment and save the comment.

/review - Manually triggers a full AI review.
/pause - Pauses automatic reviews on this pull request.
/resume - Resumes automatic reviews.
/resolve - Marks all Bito-posted review comments as resolved.
/abort - Cancels all in-progress reviews.

Refer to the documentation for additional commands.

Configuration

This repository uses Superset You can customize the agent settings here or contact your Bito workspace admin at evan@preset.io.

Documentation & Help

AI Code Review powered by

bito-code-review · 2026-05-05T16:55:06Z

Yes, the suggestion is valid — StrictMode's double-invocation in development causes the store.subscribe in EmbededLazyDashboardPage's render to create duplicate subscriptions without cleanup, leading to memory leaks and repeated observeDataMask emissions. To resolve, move the subscription logic into useEffect with cleanup: import useEffect, then wrap the subscribe call in useEffect(() => { const unsubscribe = store.subscribe(...); return unsubscribe; }, [uiConfig.emitDataMasks]). There are no other comments on this PR.

superset-frontend/src/embedded/index.tsx

import { useEffect } from 'react';

// Inside EmbededLazyDashboardPage
function EmbededLazyDashboardPage() {
  // ... existing code ...
  useEffect(() => {
    if (uiConfig.emitDataMasks) {
      let previousDataMask = store.getState().dataMask;
      const unsubscribe = store.subscribe(() => {
        const currentDataMask = store.getState().dataMask;
        if (currentDataMask !== previousDataMask) {
          previousDataMask = currentDataMask;
          Switchboard.emit('observeDataMask', ...);
        }
      });
      return unsubscribe;
    }
  }, [uiConfig.emitDataMasks]);
  // Remove the inline subscribe logic
}

netlify · 2026-05-05T17:01:43Z

✅ Deploy Preview for superset-docs-preview ready!

Name	Link
🔨 Latest commit	`893a780`
🔍 Latest deploy log	https://app.netlify.com/projects/superset-docs-preview/deploys/69fa1f712f117b0008657e4c
😎 Deploy Preview	https://deploy-preview-39893--superset-docs-preview.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.
🤖 Make changes	Run an agent on this branch

To edit notification comments on pull requests, go to your Netlify project configuration.

codecov · 2026-05-05T18:31:29Z

Codecov Report

❌ Patch coverage is 0% with 10 lines in your changes missing coverage. Please review.
✅ Project coverage is 64.38%. Comparing base (9e91ae8) to head (85f8b4c).
⚠️ Report is 41 commits behind head on master.

Files with missing lines	Patch %	Lines
superset-frontend/src/embedded/index.tsx	0.00%	7 Missing ⚠️
superset-frontend/src/views/menu.tsx	0.00%	2 Missing ⚠️
superset-frontend/src/views/index.tsx	0.00%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           master   #39893   +/-   ##
=======================================
  Coverage   64.38%   64.38%           
=======================================
  Files        2569     2569           
  Lines      134785   134786    +1     
  Branches    31295    31295           
=======================================
+ Hits        86777    86781    +4     
+ Misses      46510    46507    -3     
  Partials     1498     1498

Flag	Coverage Δ
javascript	`66.64% <0.00%> (+<0.01%)`	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

Per codeant review on #39893: subscribing to the Redux store from inside the render body of EmbededLazyDashboardPage registered a new listener on every render with no cleanup, leaking subscriptions and double-emitting observeDataMask events on each store update. StrictMode's dev-mode double-mount made the leak immediately visible. Move the subscription into a useEffect keyed on emitDataMasks, returning the Redux unsubscribe so React tears the listener down on unmount. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

bito-code-review · 2026-05-06T06:10:51Z

Code Review Agent Run #4a46a4

Actionable Suggestions - 0

Review Details

Files reviewed - 1 · Commit Range: 893a780..04dcd88
- superset-frontend/src/embedded/index.tsx
Files skipped - 0
Tools
- Whispers (Secret Scanner) - ✔︎ Successful
- Detect-secrets (Secret Scanner) - ✔︎ Successful

Bito Usage Guide

Commands

Type the following command in the pull request comment and save the comment.

/review - Manually triggers a full AI review.
/pause - Pauses automatic reviews on this pull request.
/resume - Resumes automatic reviews.
/resolve - Marks all Bito-posted review comments as resolved.
/abort - Cancels all in-progress reviews.

Refer to the documentation for additional commands.

Configuration

This repository uses Superset You can customize the agent settings here or contact your Bito workspace admin at evan@preset.io.

Documentation & Help

AI Code Review powered by

Copilot

Pull request overview

Enables React StrictMode at Superset’s three React 18 root entrypoints as a foundation for future concurrent-rendering adoption, and adjusts the embedded app to avoid render-time side effects that StrictMode would surface in development.

Changes:

Wraps the main app root mount (views/index.tsx) in <StrictMode>.
Wraps the backend-rendered menu root mount (views/menu.tsx) in <StrictMode>.
Wraps the embedded root mount in <StrictMode> and moves the Redux store.subscribe for data mask emission into a useEffect with proper cleanup.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
superset-frontend/src/views/menu.tsx	Wraps the menu-only React mount tree in `StrictMode`.
superset-frontend/src/views/index.tsx	Wraps the main application root render in `StrictMode`.
superset-frontend/src/embedded/index.tsx	Wraps embedded root render in `StrictMode` and ensures store subscriptions are established/cleaned up via `useEffect`.

Rename to EmbeddedLazyDashboardPage. Pre-existing typo flagged by Copilot review on #39893; updated both the definition and the single usage site in the same file. No other references in the codebase. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

bito-code-review · 2026-05-09T00:57:58Z

Code Review Agent Run #8e9f24

Actionable Suggestions - 0

Review Details

Files reviewed - 1 · Commit Range: 04dcd88..85f8b4c
- superset-frontend/src/embedded/index.tsx
Files skipped - 0
Tools
- Whispers (Secret Scanner) - ✔︎ Successful
- Detect-secrets (Secret Scanner) - ✔︎ Successful

Bito Usage Guide

Commands

Type the following command in the pull request comment and save the comment.

/review - Manually triggers a full AI review.
/pause - Pauses automatic reviews on this pull request.
/resume - Resumes automatic reviews.
/resolve - Marks all Bito-posted review comments as resolved.
/abort - Cancels all in-progress reviews.

Refer to the documentation for additional commands.

Configuration

This repository uses Superset You can customize the agent settings here or contact your Bito workspace admin at evan@preset.io.

Documentation & Help

AI Code Review powered by

msyavuz

LGTM!

Co-authored-by: Claude Code <noreply@anthropic.com>

pull-request-size Bot added the size/M label May 5, 2026

dosubot Bot added the change:frontend Requires changing the frontend label May 5, 2026

codeant-ai-for-open-source Bot reviewed May 5, 2026

View reviewed changes

Comment thread superset-frontend/src/embedded/index.tsx

rusackas mentioned this pull request May 7, 2026

TODO: Adopt React 18 concurrent features now that the upgrade has landed #39890

Open

6 tasks

rusackas requested review from Copilot and msyavuz May 8, 2026 17:44

Copilot started reviewing on behalf of rusackas May 8, 2026 17:45 View session

Copilot AI reviewed May 8, 2026

View reviewed changes

Comment thread superset-frontend/src/embedded/index.tsx Outdated

msyavuz approved these changes May 11, 2026

View reviewed changes

rusackas merged commit 516bb19 into master May 11, 2026
72 checks passed

rusackas deleted the feat/react-strict-mode branch May 11, 2026 16:48

qfcwell pushed a commit to qfcwell/superset that referenced this pull request May 12, 2026

feat(frontend): enable React StrictMode at root (apache#39893)

5d3c523

Co-authored-by: Claude Code <noreply@anthropic.com>

msyavuz mentioned this pull request May 12, 2026

fix: chart rendering race condition and homepage connection reset #40065

Merged

9 tasks

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

feat(frontend): enable React StrictMode at root#39893

feat(frontend): enable React StrictMode at root#39893
rusackas merged 3 commits into
masterfrom
feat/react-strict-mode

rusackas commented May 5, 2026

Uh oh!

bito-code-review Bot commented May 5, 2026 •

edited

Loading

Code Review Agent Run #541f49

Uh oh!

Uh oh!

bito-code-review Bot commented May 5, 2026

Uh oh!

netlify Bot commented May 5, 2026

Uh oh!

codecov Bot commented May 5, 2026 •

edited

Loading

Uh oh!

bito-code-review Bot commented May 6, 2026 •

edited

Loading

Code Review Agent Run #4a46a4

Uh oh!

Copilot AI left a comment

Uh oh!

Uh oh!

bito-code-review Bot commented May 9, 2026 •

edited

Loading

Code Review Agent Run #8e9f24

Uh oh!

msyavuz left a comment

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

4 participants

Conversation

rusackas commented May 5, 2026

SUMMARY

Why

Scope notes

BEFORE/AFTER SCREENSHOTS OR ANIMATED GIF

TESTING INSTRUCTIONS

ADDITIONAL INFORMATION

Uh oh!

bito-code-review Bot commented May 5, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Code Review Agent Run #541f49

Uh oh!

Uh oh!

bito-code-review Bot commented May 5, 2026

Uh oh!

netlify Bot commented May 5, 2026

✅ Deploy Preview for superset-docs-preview ready!

Uh oh!

codecov Bot commented May 5, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Codecov Report

Uh oh!

bito-code-review Bot commented May 6, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Code Review Agent Run #4a46a4

Uh oh!

Copilot AI left a comment

Choose a reason for hiding this comment

Pull request overview

Reviewed changes

Uh oh!

Uh oh!

bito-code-review Bot commented May 9, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Code Review Agent Run #8e9f24

Uh oh!

msyavuz left a comment

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

4 participants

bito-code-review Bot commented May 5, 2026 •

edited

Loading

codecov Bot commented May 5, 2026 •

edited

Loading

bito-code-review Bot commented May 6, 2026 •

edited

Loading

bito-code-review Bot commented May 9, 2026 •

edited

Loading