feat(js): Add documentation for setActiveSpanInBrowser(span: Span)

[Lms24]

DESCRIBE YOUR PR

Adds documentation for Sentry. setActiveSpanInBrowser(span) which is added via getsentry/sentry-javascript#17714. To be merged only after the feature was released. This is still based on #15006 because I need the availableSince prop on the SdkApi component.

closes https://linear.app/getsentry/issue/FE-608/docs-for-setspanactive

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Project	Deployment	Preview	Comments	Updated (UTC)
sentry-docs	Ready	Preview	Comment	Sep 26, 2025 5:01pm

1 Skipped Deployment

Project	Deployment	Preview	Comments	Updated (UTC)
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[linear]

FE-608 docs for `setSpanActive`

[codecov]

Bundle Report

Changes will increase total bundle size by 960 bytes (0.0%) ⬆️. This is within the configured threshold ✅

Detailed changes

Bundle name	Size	Change
sentry-docs-client-array-push	10.13MB	-6 bytes (-0.0%) ⬇️
sentry-docs-server-cjs	12.87MB	966 bytes (0.01%) ⬆️

Affected Assets, Files, and Routes:

view changes for bundle: sentry-docs-client-array-push

Assets Changed:

Asset Name	Size Change	Total Size	Change (%)
static/chunks/pages/_app-*.js	-3 bytes	882.71kB	-0.0%
static/chunks/8321-*.js	-3 bytes	425.87kB	-0.0%
server/middleware-*.js	6.46kB	7.46kB	645.5% ⚠️
server/middleware-*.js	-6.46kB	1.0kB	-86.59%
static/2MbOsBZoXOy48Nim4jWW6/_buildManifest.js (New)	684 bytes	684 bytes	100.0% 🚀
static/2MbOsBZoXOy48Nim4jWW6/_ssgManifest.js (New)	77 bytes	77 bytes	100.0% 🚀
static/xhCiGLnCakcwwMLfNybxs/_buildManifest.js (Deleted)	-684 bytes	0 bytes	-100.0% 🗑️
static/xhCiGLnCakcwwMLfNybxs/_ssgManifest.js (Deleted)	-77 bytes	0 bytes	-100.0% 🗑️

view changes for bundle: sentry-docs-server-cjs

Assets Changed:

Asset Name	Size Change	Total Size	Change (%)
1729.js	-3 bytes	1.78MB	-0.0%
../instrumentation.js	-3 bytes	1.1MB	-0.0%
9523.js	-3 bytes	1.08MB	-0.0%
../app/[[...path]]/page.js.nft.json	325 bytes	826.42kB	0.04%
../app/platform-redirect/page.js.nft.json	325 bytes	826.33kB	0.04%
../app/sitemap.xml/route.js.nft.json	325 bytes	823.56kB	0.04%

[s1gr1d]

I am not sure if this is correct. startSpanManual also needs to be manually ended, right? Or do I get this sentence wrong 🤔

After reading it some times again I think you mean that startSpanManual is only an active span during the callback, even though it can be ended after the callback. Maybe we can write that a bit differently.

"Even though a span can be ended outside the callback of startSpanManual, the span continues as inactive outside of the callback. With setActiveSpan a span can be set active until you manually end the span."

[Lms24]

thanks for calling this out! I reworded this entire section. Hope it reads a bit better now :)

[sfanahata]

Yay! Looks good.