v8.21.2

What's Changed

• chore(release): update scripts for other git configs and backports by @wjhsf in #5454
• build(deps-dev): bump the theoretically-non-breaking group with 4 updates by @dependabot[bot] in #5456
• fix: remove redundant optional chaining on process.env which is breaking testing by @jhefferman-sfdc in #5459
• chore: bump version to 8.21.2 by @jye-sf in #5461
• chore: release v8.21.2 by @jye-sf in #5462

Full Changelog: v8.21.1...v8.21.2

v8.21.1

What's Changed

• chore: bump version to 8.21.0 by @jmsjtu in #5445
• build(deps-dev): bump the theoretically-non-breaking group with 4 updates by @dependabot[bot] in #5444
• chore: update nucleus config CLCO master by @jmsjtu in #5447
• fix: check process is defined in ssr-client-utils by @jhefferman-sfdc in #5449

Full Changelog: v8.20.3...v8.21.1

v8.20.4

What's Changed

• (258) fix: check process is defined by @jhefferman-sfdc in #5451

Full Changelog: v8.20.3...v8.20.4

v8.20.3

What's Changed

• chore: remove dead code by @wjhsf in #5435
• chore(release): adjust scripts to fix minor bugs by @wjhsf in #5431
• chore(scripts): canary release script should use canary dist tag by @wjhsf in #5436
• test(wtr): get another pile of tests passing by @wjhsf in #5425
• chore(scripts): update license check to be more flexible @W-19066903 by @wjhsf in #5422
• fix: dudupe light scoped issue, hydration coverage by @jhefferman-sfdc in #5438
• chore: bump version to 8.20.3 by @jhefferman-sfdc in #5441
• Release publish 2025 08 04 16 57 by @jhefferman-sfdc in #5442

v8.20.2

What's Changed

• test(ts): add assertion so we don't accidentally bump TS again @W-18978621 by @wjhsf in #5410
• test(web-test-runner): run hydration tests in CI @W-18780671 by @wjhsf in #5398
• chore(ci): run perf testing on release branches @W-18882666 by @wjhsf in #5408
• test(integration): add missing bits to make more tests pass @W-18763051 by @wjhsf in #5411
• test(integration): more web-test-runner test fixes @W-18763051 by @wjhsf in #5414
• build(deps): bump the theoretically-non-breaking group across 1 directory with 41 updates by @dependabot[bot] in #5413
• build(deps-dev): bump dotenv from 16.5.0 to 17.2.0 by @dependabot[bot] in #5417
• build(deps-dev): bump parse5 from 7.3.0 to 8.0.0 by @dependabot[bot] in #5418
• build(deps): bump form-data from 4.0.1 to 4.0.4 by @dependabot[bot] in #5424
• fix(types): add synthetic prop to component template by @wjhsf in #5426
• docs: architecture.md preview. by @TitanCmd in #5427
• chore: bump version to 8.20.2 by @wjhsf in #5430
• chore: release 8.20.2 by @wjhsf in #5434

New Contributors

• @TitanCmd made their first contribution in #5427

Full Changelog: v8.20.1...v8.20.2

v8.20.1

What's Changed

• feat(ts): almost enable TypeScript in the playground by @wjhsf in #5384
• test(integration): begin moving from Karma to Web Test Runner by @wjhsf in #5386
• @W-17388345 - add context support to ssrv2 component lifecycle by @jhefferman-sfdc in #5387
• chore: create missing OSS files @W-18819307 by @wjhsf in #5388
• chore(dependabot): separate all webdriverio versions and add group for vitest by @wjhsf in #5390
• chore(deps): add tslib to playground by @wjhsf in #5391
• chore(deps): bump @types/estree and parse5 by @wjhsf in #5392
• build(deps-dev): bump the nx group with 2 updates by @dependabot in #5393
• build(deps-dev): bump the best group with 3 updates by @dependabot in #5395
• feat: export add trusted context by @jhefferman-sfdc in #5399
• fix: expose additional signals api by @jhefferman-sfdc in #5402

Full Changelog: v8.20.0...v8.20.1

v8.20.0

What's Changed

• chore: remove structuredClone workaround by @wjhsf in #5367
• fix(release): oops shell scripts are relative to cwd by @wjhsf in #5368
• build(deps): bump undici from 6.21.1 to 6.21.3 by @dependabot in #5373
• test(engine-server): update global attributes spec by @ekashida in #5378
• feat(ssr): make SSR compiler recognize lwc:on directive @W-18158832 by @gaurav-rk9 in #5377
• fix(ssr): massive compiled outputs when nested slots are present by @divmain in #5379
• chore: bump version to 8.20.0 by @wjhsf in #5381
• chore: release 8.20.0 by @wjhsf in #5382

New Contributors

• @gaurav-rk9 made their first contribution in #5377

Full Changelog: v8.19.1...v8.20.0

v8.19.1

What's Changed

• feat: CSR/SSRv1 context by @jhefferman-sfdc in #5356

v8.19.0

Better types for template elements

TypeScript component authors can now specify a new property, __lwc_public_property_types__, to indicate to TypeScript which properties are available on the element created by a component. This prevents erroneous property definitions, which are otherwise unavoidable due to the way that TypeScript implements decorators.

Example

// <c-inferred-props>
class InferredProps extends LightningElement {
  @api exposed = 'hello'
  internal = 'secret'
}

// <c-explicit-props>
class ExplicitProps extends InferredProps {
  __lwc_public_property_types__?: {
    exposed: string
  }
}

class Container extends LightningElement {
  checkInferred() {
    const inferred = this.querySelector<LightningHTMLElement<InferredProps>>('c-inferred-props')!
    inferred.exposed // ✅ Valid, no type error
    inferred.internal // ❌ Invalid, but no type error!
  }

  checkExplicit() {
    const explicit = this.querySelector<LightningHTMLElement<ExplicitProps>>('c-explicit-props')!
    explicit.exposed // ✅ Valid, no type error
    explicit.internal // ✅ Invalid, and a type error occurs!
  }
}

In this example, the element interface for c-inferred-props is defined by LightningHTMLElement<InferredProps>. That interface has an erroneous property definition, internal. The internal property is part of the component interface, but is not decorated with @api, so it should not be part of the element interface.

The element interface for c-explicit-props is defined by LightningHTMLElement<ExplicitProps>. Because ExplicitProps defines __lwc_public_property_types__, the element interface does not include the internal property, which is the correct behavior.

What else changed?

• feat: make it pop! (over) @W-18425406 by @wjhsf in #5357
• chore: add summer25 def to nucleus.yaml by @jhefferman-sfdc in #5365
• feat(types): add hidden helper to make inferring element types better @W-18442478 by @wjhsf in #5362
• chore: bump version to 8.19.0 by @wjhsf in #5370
• chore: release 8.19.0 by @wjhsf in #5371

Full Changelog: v8.18.2...v8.19.0

v8.16.5

What's Changed

• fix: remove perf regression for signals re-enablement (256 patch) by @jhefferman-sfdc in #5358