After editing relations, unable to load content items

[PeterBowater]

Update from Strapi

we have a fix for this issue and will release it as part of our normal update cycle on Wednesday July 15th, 2026

Due to holidays in most of the countries our engineers operate from we generally avoid pushing out of cycle hot fixes if we have a coverage gap immediately following, hence why we are not releasing it today.

Thank you for your patience

---

Node Version

22

Package Manager

yarn

Package Manager Version

yarn@1.22.22

Strapi Version

5.50.1

Operating System

Strapi Cloud

Database

Strapi Cloud

Javascript or Typescript

Typescript

Reproduction URL

No response

Bug Description

Locally this appears to be working fine, on Cloud we are seeing issues when opening a content item after having moved some related items around.

We get a modal prompt with:

Unrecognized extension value in extension set ([object Object]). This sometimes happens because multiple instances of @codemirror/state are loaded, breaking instance of checks.

This refers to the following code:

function c7n(t, e, n) { let r = [[], [], [], [], []] , i = new Map; function s(o, a) { let l = i.get(o); if (l != null) { if (l <= a) return; let c = r[l].indexOf(o); c > -1 && r[l].splice(c, 1), o instanceof e0e && n.delete(o.compartment) } if (i.set(o, a), Array.isArray(o)) for (let c of o) s(c, a); else if (o instanceof e0e) { if (n.has(o.compartment)) throw new RangeError("Duplicate use of compartment in extensions"); let c = e.get(o.compartment) || o.inner; n.set(o.compartment, c), s(c, a) } else if (o instanceof Bct) s(o.inner, o.prec); else if (o instanceof zu) r[a].push(o), o.provides && s(o.provides, a); else if (o instanceof gV) r[a].push(o), o.facet.extensions && s(o.facet.extensions, rE.default); else { let c = o.extension; if (!c) throw new Error(Unrecognized extension value in extension set (${o}).); if (c == o) throw new Error(Unrecognized extension value in extension set (${o}). This sometimes happens because multiple instances of @codemirror/state are loaded, breaking instanceof checks.); s(c, a) } } return s(t, rE.default),

Once we have had this error we then can't open up ANY of the collection's content items, see the error seems to stick.

Steps to Reproduce

We are unable to reproduce locally at all, only on our Cloud hosted instance, though I don't feel it relevant.

Expected Behavior

No error, and content item opens

Logs

No logs for errors on cloud.

Browser: 

strapi-DCiKEcZM.js:3645 Error: Unrecognized extension value in extension set ([object Object]). This sometimes happens because multiple instances of @codemirror/state are loaded, breaking instanceof checks.

strapi-DCiKEcZM.js:556 Error: Unrecognized extension value in extension set ([object Object]). This sometimes happens because multiple instances of @codemirror/state are loaded, breaking instanceof checks.

strapi-DCiKEcZM.js:3498 React Router caught the following error during render Error: Unrecognized extension value in extension set ([object Object]). This sometimes happens because multiple instances of @codemirror/state are loaded, breaking instanceof checks.

Code Snippets

No response

Media

No response

Additional information

No response

Confirmation Checklist

• I have checked the existing issues for duplicates.
• I agree to follow this project's Code of Conduct.

[github-actions]

This is a templated message

Hello @PeterBowater,

We ask that you please follow the issue template.
A proper issue submission lets us better understand the origin of your bug and therefore help you. You can see the template guidelines for bug reports here.

Please create a new issue and completely fill out the issue template, you can open a new issue here.

Thank you.

[PeterBowater]

Adding to this, we have rolled back to 5.49 and continue to face the issue, have raised separately with Strapi Cloud support in case it is related.