fix(insights): stop add-to-dashboard modal from wiping other dashboards

[posthog]

Problem

The add-insight-to-dashboard modal (addSavedInsightsModalLogic.ts) has two bugs on a heavily used path:

• The add/remove listeners PATCH a dashboards array built from insight.dashboards. That field is deprecated and the API stopped serving it to session-authenticated callers, so the value is always undefined in the modal. The PATCH goes out with just the one dashboard ID, and the backend treats that as the complete desired set - silently detaching the insight from every other dashboard it was already on.
• The post-toggle dashboard refresh mounts a fresh dashboardLogic({id}) instance, fires loadDashboard, then immediately unmounts it. loadDashboard's loader awaits breakpoint(200) before doing anything, so the unmount can tear the logic down mid-flight and the dashboard can be left showing stale/empty state even though the add succeeded. Passing a narrower props object also risks clobbering the props already set on the scene's mounted dashboardLogic instance.
• On top of that, the modal only fires a closed capture event with no matching opened event, so this whole path had no conversion signal to catch it.

Changes

• Derive the insight's current dashboard membership from dashboard_tiles (still served by the API, unlike the deprecated dashboards field) instead of the always-undefined field, for both add and remove.
• Reuse the dashboard's own mounted dashboardLogic via .findMounted(...) instead of mounting/unmounting a transient instance.
• Add an insight dashboard modal - opened capture alongside the existing close event.

How did you test this code?

Added a parameterized Jest test in addSavedInsightsModalLogic.test.ts covering both addInsightToDashboard and removeInsightFromDashboard, asserting the PATCH payload preserves the insight's other dashboard memberships. Verified it fails against the pre-fix code (loses a dashboard on add) and passes with the fix. Ran the full existing suite for this logic file - all 16 tests pass.

Also ran pnpm --filter=@posthog/frontend typescript:check and pnpm --filter=@posthog/frontend fix (lint + format) against the changed files, and hogli ci:preflight --fix (clean, no findings).

I wasn't able to manually exercise the modal in a running dev environment for this change.

Automatic notifications

• Publish to changelog?
• Alert Sales and Marketing teams?

Docs update

N/A - no user-facing behavior change beyond the bug fix; no documented workflow affected.

🤖 Agent context

Autonomy: Fully autonomous

• Investigated via a research subagent to confirm the exact backend serializer behavior for dashboards vs dashboard_tiles (products/product_analytics/backend/api/insight.py) before deciding the fix - confirmed dashboard_tiles is read-only server-side, so the write path still has to go through the deprecated dashboards field, just computed from a reliable source.
• Skill invoked: /writing-tests before adding the regression test.
• Considered adding an explicit confirm button and reworking the toggle UX per the inbox report's broader suggestion, but scoped this PR to the two concrete defects behind the observed symptoms (silent detachment, stuck-empty refresh) rather than a UX redesign.
• Checked for competing work first (open PRs/issues by file path and keywords) - found none.

---

Created with PostHog Desktop from this inbox report.

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[github-actions]

🤖 CI report

⚠️ Bundle size — 🔺 +116 B (+0.0%)

Uncompressed size of every built .js bundle, compared against the base branch.

Total: 65.51 MiB · 🔺 +116 B (+0.0%)

No file changed by more than 1000 B.

_{Posted automatically by build-bundle-size-report · uncompressed bytes from dist-report}

✅ Eager graph — within budget

How much code each root ships on the eager path — downloaded and parsed before the surface is interactive. Measured from the esbuild output chunks (post-tree-shake, static imports only); lazy import() / React.lazy chunks are not counted.

Root	Eager (shipped)	Δ vs base	Budget
entry (logged-out pages, app bootstrap) src/index.tsx	1.25 MiB · 22 files	no change	███░░░░░░░ 27.7% of 4.51 MiB
authenticated shell (every logged-in page) src/scenes/AuthenticatedShell.tsx	8.13 MiB · 3,035 files	🔺 +113 B (+0.0%)	████████░░ 83.8% of 9.71 MiB

🟢 node_modules/monaco-editor/ stays out of src/index.tsx
🟢 src/lib/components/ActivityLog/describers stays out of src/index.tsx
🟢 [object Object] stays out of src/index.tsx
🟢 [object Object] stays out of src/index.tsx
🟢 node_modules/monaco-editor/ stays out of src/scenes/AuthenticatedShell.tsx
🟢 src/lib/components/ActivityLog/describers stays out of src/scenes/AuthenticatedShell.tsx
🟢 [object Object] stays out of src/scenes/AuthenticatedShell.tsx
🟢 [object Object] stays out of src/scenes/AuthenticatedShell.tsx

Largest files eagerly shipped from src/index.tsx

Size	File
126.8 KiB	../node_modules/.pnpm/react-dom@18.3.1_react@18.3.1/node_modules/react-dom/cjs/react-dom.production.min.js
24.6 KiB	../node_modules/.pnpm/buffer@6.0.3/node_modules/buffer/index.js
6.3 KiB	../node_modules/.pnpm/react@18.3.1/node_modules/react/cjs/react.production.min.js
4.5 KiB	../node_modules/.pnpm/@jspm+core@2.1.0/node_modules/@jspm/core/nodelibs/browser/process.js
3.9 KiB	../node_modules/.pnpm/scheduler@0.23.2/node_modules/scheduler/cjs/scheduler.production.min.js
1.4 KiB	../node_modules/.pnpm/base64-js@1.5.1/node_modules/base64-js/index.js
1.3 KiB	src/RootErrorBoundary.tsx
912 B	../node_modules/.pnpm/ieee754@1.2.1/node_modules/ieee754/index.js
789 B	src/scenes/ChunkLoadErrorBoundary.tsx
762 B	src/index.tsx

Largest files eagerly shipped from src/scenes/AuthenticatedShell.tsx

Size	File
285.6 KiB	../node_modules/.pnpm/posthog-js@1.409.5/node_modules/posthog-js/dist/rrweb.js
267.7 KiB	../node_modules/.pnpm/@posthog+icons@0.38.0_react-dom@18.3.1_react@18.3.1__react@18.3.1/node_modules/@posthog/icons/dist/posthog-icons.es.js
235.5 KiB	src/taxonomy/core-filter-definitions-by-group.json
231.5 KiB	../node_modules/.pnpm/posthog-js@1.409.5/node_modules/posthog-js/dist/module.js
154.3 KiB	../node_modules/.pnpm/re2js@0.4.1/node_modules/re2js/build/index.esm.js
126.8 KiB	../node_modules/.pnpm/react-dom@18.3.1_react@18.3.1/node_modules/react-dom/cjs/react-dom.production.min.js
105.3 KiB	src/lib/api.ts
94.7 KiB	../packages/quill/packages/quill/dist/index.js
93.3 KiB	../node_modules/.pnpm/prosemirror-view@1.40.1/node_modules/prosemirror-view/dist/index.js
90.6 KiB	../node_modules/.pnpm/@tiptap+core@3.20.6_@tiptap+pm@3.20.6/node_modules/@tiptap/core/dist/index.js

_{Posted automatically by check-eager-graph · sizes are eager output bytes (shipped, post-tree-shake) from the esbuild metafile · part of #32479}

✅ Toolbar bundle — eager 2.19 MiB within budget

What the toolbar ships to customer pages, measured from the esbuild output (minified, post-tree-shake). The eager set is the entry plus everything statically imported from it — fetched before any feature runs; deferred chunks load lazily. The eager guardrail is 5.72 MiB. Each output file must also stay below 10 MB, where CloudFront stops compressing it. The module boundary is enforced separately by check-toolbar-graph.

Metric	Size	Δ vs base	Budget
Eager (shipped) entry + static imports	2.19 MiB · 17 files	no change	████░░░░░░ 38.3% of 5.72 MiB
Deferred (lazy)	2.08 MiB · 33 files	no change	n/a — loads on demand
Loader dist/toolbar.js	1.1 KiB	no change	█░░░░░░░░░ 5.8% of 19.5 KiB

Largest eagerly-shipped chunks

Size	File
718.3 KiB	dist/toolbar/toolbar-app-FT4UJ3IP.css
551.4 KiB	dist/toolbar/chunk-chunk-AGSGCCBT.js
484.6 KiB	dist/toolbar/chunk-chunk-T44C2V5C.js
133.6 KiB	dist/toolbar/chunk-chunk-KBLX73CM.js
131.8 KiB	dist/toolbar/chunk-chunk-T5KY5WYR.js
71.0 KiB	dist/toolbar/toolbar-app-FKUW2FOM.js
69.0 KiB	dist/toolbar/chunk-chunk-27JL52RE.js
35.6 KiB	dist/toolbar/chunk-chunk-3JVI3ZTF.js
20.9 KiB	dist/toolbar/chunk-chunk-HJ3ZJMTU.js
12.2 KiB	dist/toolbar/chunk-chunk-PIK3PADE.js

_{Posted automatically by check-toolbar-size · sizes are toolbar output bytes (shipped, post-tree-shake) from the esbuild metafile}

✅ Dist folder size — 🔺 +2.4 KiB (+0.0%)

Total size of the built frontend/dist folder (all assets), compared against the base branch.

Total: 1381.31 MiB · 🔺 +2.4 KiB (+0.0%)

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