[kumo] Remove unused Tabs entrance styles

[mattrothenberg]

Summary

• remove the unused Tabs indicator entrance-animation classes
• preserve the existing translate-based tab-to-tab indicator transition
• keep the indicator's current initial-render behavior unchanged

The removed selector targeted a data-rendered attribute that Base UI's Tabs indicator does not emit, so the styles were unreachable. This is the smaller alternative to restoring a separate entrance animation in #839.

Validation

• vp lint src/components/tabs

• git diff --check

• Reviews

• bonk has reviewed the change

• automated review not possible because: this is a one-line removal of an unreachable CSS selector

• Tests

• Tests included/updated

• Automated tests not possible - manual testing has been completed as follows: not applicable

• Additional testing not necessary because: Base UI never emits the targeted attribute, so removing the selector does not change runtime behavior

[ask-bonk]

LGTM!

Review notes

• Confirmed the review target is PR [kumo] Remove unused Tabs entrance styles #841. I’m inspecting the Tabs implementation, package guidance, pull-request patch, and existing review feedback before assessing behavior.
• Verified the PR metadata, head SHA, and two-file patch from GitHub; the only implementation change removes the data-[rendered=false] indicator classes at tabs.tsx:272. No existing reviews or inline comments are present.
• The component’s local tests cover link rendering and overflow controls, not the removed styling state. The lockfile resolves @base-ui/react to 1.8.0.
• The checked-out workspace has no local modifications. The requested lint command could not run because pnpm is unavailable in this runner; I’m using the published Base UI package source to complete the runtime-attribute check.
• Base UI 1.8.0’s TabsIndicator source and API documentation confirm that it sets hidden until layout is settled and emits orientation/activation-direction attributes, but never data-rendered. The retained width/translate transition classes continue to govern indicator movement.
• No actionable behavioral, accessibility, compatibility, or release-management issues were identified. No inline review comment was submitted.

github run

[pkg-pr-new]

npm i https://pkg.pr.new/@cloudflare/kumo@841

commit: a826bac

[github-actions]

Visual contracts

Linux Chromium references exercised by the PR's visual-contracts job.

1 curated contract

truncating text trigger

[cloudflare-workers-and-pages]

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[github-actions]

📐 Bundle Size

Consumer fixtures bundled against packages/kumo/dist (peers external, minified ESM).

Fixture	Raw	Gzip	Brotli
Button (root)	166.3 KB	50.9 KB	44.1 KB
Button (components/button)	166.2 KB	50.9 KB	44.1 KB
Button + Dialog + Select (root)	291.1 KB	86.8 KB	72.9 KB
Button + Dialog + Select (component subpaths)	291.1 KB	86.8 KB	72.8 KB
Chart (root)	238.6 KB	72.0 KB	61.8 KB
Chart (components/chart)	238.6 KB	72.0 KB	61.9 KB
Badge (components/badge)	36.5 KB	12.7 KB	11.1 KB
Flow (components/flow)	200.6 KB	59.2 KB	51.7 KB
Button (primitives/button)	12.2 KB	4.4 KB	3.9 KB
Primitives barrel	635.8 KB	176.8 KB	139.3 KB
Code highlighting (code)	2.07 MB	469.2 KB	350.4 KB

npm tarball: 546 files, 1.50 MB packed, 6.94 MB unpacked.

⚠️ 24 flagged files in tarball (tests / raw scripts)

• dist/blocks-source/delete-resource/delete-resource.test.tsx
• dist/blocks-source/resource-list/resource-list.test.tsx
• scripts/component-registry/cache.ts
• scripts/component-registry/discovery.ts
• scripts/component-registry/example-cleanup.ts
• scripts/component-registry/index.test.ts
• scripts/component-registry/index.ts
• scripts/component-registry/markdown-generator.ts
• scripts/component-registry/metadata.ts
• scripts/component-registry/props-filter.ts
• scripts/component-registry/schema-generator.ts
• scripts/component-registry/sub-components.ts
• scripts/component-registry/types.ts
• scripts/component-registry/utils.ts
• scripts/component-registry/variant-parser.ts
• scripts/css-build.ts
• scripts/generate-globe-land-mask.mjs
• scripts/generate-primitives.ts
• scripts/theme-generator/config.ts
• scripts/theme-generator/generate-css.test.ts
• scripts/theme-generator/generate-css.ts
• scripts/theme-generator/index.ts
• scripts/theme-generator/migrate.ts
• scripts/theme-generator/types.ts

Report-only: no size thresholds are enforced yet.

Commit: a826bac3