# Kibana unexpected session error in Firefox only

**URL:** <https://discuss.elastic.co/t/kibana-unexpected-session-error-in-firefox-only/377999>\
**Category:** Kibana\
**Created:** [May 9, 2025, 5:28pm UTC](https://discuss.elastic.co/t/kibana-unexpected-session-error-in-firefox-only/377999 "2025-05-09T17:28:57Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![natharran](https://avatars.discourse-cdn.com/v4/letter/n/7feea3/32.png) [@natharran](https://discuss.elastic.co/u/natharran)\
**Post date:** [May 9, 2025, 5:28pm UTC](https://discuss.elastic.co/t/kibana-unexpected-session-error-in-firefox-only/377999/1 "2025-05-09T17:28:57Z")

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I have Elasticsearch and Kibana (8.17.4) under ECK (3.0.0) in Kubernetes. I'm not overwriting any ECK-managed settings for either ES or Kibana. In Firefox 138.0.1 I'm experiencing a weird issue: Kibana logs out on refresh or even on opening a dashboard with "Unexpected session error". It only happens in Firefox. I have standard configuration and all extensions disabled. Sometimes it works OK, sometimes not, but sooner or later this happens (within minutes).

Then I have another installation out of Kubernetes and the same problem takes place there, too.

In Network section in Firefox devtools I see this error: NS\_BINDING\_ABORTED. This doesn't show in other browsers. But as I've said, I haven't done any particular tweaking to my Firefox installation.

Is there a way to fix it on my end? Or should I report this as a bug?

Thank you.

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<div class="post-metadata">

**Author:** ![natharran](https://avatars.discourse-cdn.com/v4/letter/n/7feea3/32.png) [@natharran](https://discuss.elastic.co/u/natharran)\
**Post date:** [May 9, 2025, 5:32pm UTC](https://discuss.elastic.co/t/kibana-unexpected-session-error-in-firefox-only/377999/2 "2025-05-09T17:32:06Z")

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Oh and I should also add that neither Kibana nor ES logs contain any information about this error (which makes sense as it obviously happens in Firefox).

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**Author:** ![Larry\_Gregory](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/larry_gregory/32/34969_2.png) [@Larry\_Gregory](https://discuss.elastic.co/u/Larry_Gregory)\
**Post date:** [May 9, 2025, 6:21pm UTC](https://discuss.elastic.co/t/kibana-unexpected-session-error-in-firefox-only/377999/3 "2025-05-09T18:21:52Z")

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Hey folks,

We've identified the issue as a regression in Firefox which does not play nicely with the way Kibana manages its session cookie. We have a fix in progress on the Kibana side to workaround the problem, and we've filed a bug report with Mozilla as well:

- [Unexpected logouts from Kibana dashboards in Firefox · Issue #220637 · elastic/kibana · GitHub](https://github.com/elastic/kibana/issues/220637)
- [1965056 - Cache re-validation request includes duplicated cookies](https://bugzilla.mozilla.org/show_bug.cgi?id=1965056)