@clerk/nextjs 7.2.8 breaks

[CodingFabian]

Preliminary Checks

• I have reviewed the documentation: https://clerk.com/docs

• I have searched for existing issues: https://github.com/clerk/javascript/issues

• I have not already reached out to Clerk support via email or Discord (if you have, no need to open an issue here)

• This issue is not a question, general help request, or anything other than a bug report directly related to Clerk. Please ask questions in our Discord community: https://clerk.com/discord.

Description

After Upgrading 7.2.7 to 7.2.8 our website broke:

TypeError: e.isFetched is not a function. (In 'e.isFetched()', 'e.isFetched' is undefined)

Claude investigated this:

Root cause: The @clerk/nextjs@7.2.7 → 7.2.8 bump brought in @clerk/shared@4.8.6, which changed its @tanstack/query-core dependency from the exact pin 5.90.16 to the range ^5.90.16. That resolved to 5.100.6, which added isFetched() as a new method on the Query class and has the QueryObserver call query.isFetched().

Why only production: Clerk's production JS SDK (loaded when __client_uat cookie is present) bundles its own @tanstack/query-core internally (an older version without isFetched()). When @clerk/shared@4.8.6's QueryObserver (from 5.100.6) tries to observe queries from that bundled QueryClient, it calls query.isFetched() on a Query object that doesn't have that method → undefined is not a function.

[keepforever]

I experienced the same issue when I bumped as follows:

@clerk/react-router               ^3.1.7  →    ^3.1.8

I also noticed that if I bump react-query deps to ^5.100.6, while keeping @clerk/react-router: ^3.1.7, I get the same error.

@tanstack/react-query           ^5.100.5  →  ^5.100.6
 @tanstack/react-query-devtools  ^5.100.5  →  ^5.100.6