• PERF: DayGrid with large number of events, when dayMaxEvents:true (limited by natural row height), only a necessary subset of events will be DOM-inserted, not all
  • BREAKING: As a result, a subset of events will be run through event render hooks like eventContent
• DayGrid event slicing
  • FEATURE: Better event packing, including smarter positioning decisions for fewer slices
  • FEATURE: Related slices have more similar y-coordinates
  • FIX: Events unnecessarily going to +more link when higher-level slot would accommodate
• TimeGrid event positioning
  • FIX: Events with custom ordering and eventOrderStrict:true can overlap with slotEventOverlap: false (#7914)
  • FIX: Overlapping events can have tiny width when event content not visible (#7879)
• FIX: In Timeline and TimeGrid, when custom eventOrder, DOM order respects start-time first, then eventOrder. Better for a11y and tabbing through events sequentially
• FIX: React StrictMode: DayGrid events permanently invisible (#8088)

• FIX: Timeline view, smoother virtualized fast scrolling, especially with trackpad and especially while scrolling up with irregular height resource rows
• FIX: Timeline view, account for DST in timeslots (#7620)
• FIX: Resource TimeGrid/DayGrid, filterResourcesWithEvents should exclude columns (#6149)

• FEATURE: Print renders business-hours for print-previews that enable it
• FIX: Better page-wrapping of tall DayGrid rows with many events
• FIX: Better page-wrapping of tall Resource-Timeline rows with many events
• FIX: Events are not visible when we print using window.print() (#8097)

• PERF: General improvements with option-changes. Users of @fullcalendar/preact must upgrade their preact peer dependency to >=10.29.8
• FIX: Screen-reader improvement for Resource-Timeline timeline header text

• A failure inside the WebAssembly codec is now reported as the error it is instead of surfacing as RangeError: offset is out of bounds. The deflate_process, inflate_process and inflate9_process functions pack the number of bytes produced in the low 24 bits and the zlib status code in the top byte, but their two error paths returned a bare negative code, read as 16777214 bytes produced and copied out of the module heap into a 64KB buffer. Reaching it takes the codec running out of its fixed 16MB heap, which needs useCompressionStream and useWebWorkers both set to false, so that every entry shares one module instance, and maxWorkers raised above the number of streams the heap holds, 42 measured when compressing at level 6
• The compress direction of the WebAssembly codec now checks the status code the codec returns, which only the decompress direction did. A failed deflate() reports no byte produced and no byte consumed, which the loop reads as the end of the data, so the rest of the entry was dropped without an error. The status is also checked before the number of bytes produced is used, so a status code can no longer be read as a byte count whatever the codec returns

• New test asserting that the vendored WebAssembly module packs its error codes the way the codec expects. The module is vendored as a binary, so nothing else in the suite would notice it being re-vendored stale

• ERR_INVALID_CRC32 and ERR_INVALID_AUTHENTICATION_CODE now hold distinct values, "Invalid CRC32" and "Invalid authentication code". Both were aliases of ERR_INVALID_SIGNATURE since v2.8.44, added as aliases so the two errors could be told apart later without breaking the code comparing them at the time. ERR_INVALID_SIGNATURE is removed, the term naming a CRC-32 check and an AES authentication code, neither of which is a signature. Code comparing an error message to it must now compare to the constant naming the check that failed
• The externalFileAttribute and internalFileAttribute names are removed, from the entry properties and from the writer options. They were renamed to externalFileAttributes and internalFileAttributes in January 2025 and kept as aliases since. The other names deprecated in the 2.8 releases are kept. The minified files shrink by 354 bytes

• Deflate64 entries are no longer refused when a match at least as long as the 64KB output buffer of the WebAssembly codec starts on its boundary. The codec then fills a whole buffer without consuming any input, which was read as the end of the data: the rest of the chunk was dropped, and the entry failed with a Z_BUF_ERROR at the default chunk size, or with an invalid uncompressed size when the chunks were small enough for the loss to pass unnoticed until the end. Only Deflate64 allows such a match, its maximum length being 65538 bytes against the 258 of Deflate, and 7-Zip does not produce one, its Deflate64 encoder capping the matches at 257 bytes. The JavaScript codec was unaffected
• The JavaScript codec no longer corrupts the data when a match wraps around the end of the sliding window and ends inside it. The bytes were then copied from the output buffer instead of the window, which needs more than 32KB already decompressed and a match straddling the wrapping point. deflate and gzip reported the corruption as an invalid checksum, deflate-raw returned the expected number of bytes with a few of them wrong. The entries of a zip file are read as deflate-raw and checkCrc32 is not set by default, so the wrong bytes were returned with no error at all. The codec is the one the index-native and legacy builds use, including to read Deflate64

• The WebAssembly codec is now built from Chromium's fork of zlib, which reads 20% faster and writes 6 to 8% faster. The compressed output is unchanged, byte for byte, at every level. The module grows by 1592 bytes. The codec is used when the CompressionStream API is unavailable or turned off with the useCompressionStream option, and always when reading Deflate64 (#677)

• The keepOrder option no longer claims that setting it to true improves the use of web workers, which is the opposite of what it does. Keeping the order writes the entries one after another, so concurrent calls to add() compress one entry at a time. The remark now says so and points to bufferedWrite, which restores the concurrency while still keeping the order

• New test covering a Deflate64 match starting on the boundary of the output buffer, in both codecs
• New test covering a match wrapping around the end of the sliding window of the JavaScript codec, in both codecs
• The test pinning the attribute names now covers the precedence of the entry options over the writer options instead of the removed aliases

• Thanks to @xqdoo00o for reporting that Chromium's fork of zlib compresses faster than the one the WebAssembly codec was built from (#677)

• Turbopack: fix source field in CSS sourcemaps: #88225
• fix: track dynamic accesses in final runtime prerenders: #98255
• docs: add API reference pages for skipProxyUrlNormalize and skipTrailingSlashRedirect: #97967

Huge thanks to @Xanaado, @lubieowoce, and @icyJoseph for helping!

Release 2026-09-04 22:28

• solid-query: sweep X-Revalidate keys in the single-flight consumer (#11394) (f41ac714d) by @ryansolid

• @tanstack/solid-query@6.0.0-rc.3
• @tanstack/solid-query-devtools@6.0.0-rc.3
• @tanstack/solid-query-persist-client@6.0.0-rc.3

Release 2026-09-04 22:28

• solid-query: sweep X-Revalidate keys in the single-flight consumer (#11394) (f41ac714d) by @ryansolid

• @tanstack/solid-query@6.0.0-rc.3
• @tanstack/solid-query-devtools@6.0.0-rc.3
• @tanstack/solid-query-persist-client@6.0.0-rc.3

• Updated dependencies [f41ac71]:
  • @tanstack/solid-query@6.0.0-rc.3

• Updated dependencies [f41ac71]:
  • @tanstack/solid-query@6.0.0-rc.3

• Updated dependencies [f41ac71]:
  • @tanstack/solid-query@6.0.0-rc.3

• #11394 f41ac71 - Sweep X-Revalidate keys in the single-flight consumer. A mutation can declare its invalidation scope with Solid's reload/redirect revalidate option; the flight payload covers what the server recomputed, and whatever a declared key matches beyond it (parameterized instances only the client holds, queries no loader owns) is now invalidated client-side — active queries refetch in the background, inactive ones are marked stale. Keys match by queryKey prefix, mirroring Solid Router's consumption of the same header.