I expect that the requested site will be open
Sometimes when I'm logged in and request for example the Search or Dashboard it redirects
me to the error page with the message "n is undefined" (See Screenshot)

Please note that this bug only appears sometimes and not always.
Can you post more of the included stack trace? If it is not shown properly on the page, could you please check your browser's JS console? Ideally, repeat the step that triggers the error while the console is open.
Here is the stack trace:
n is undefined
Stack Trace:
osx3epUg/os<@https://graylog.local/assets/ExtendedSearchPage.ee54c4a9a01f2cd94626.js:1:174393
m/<@https://graylog.local/assets/app.ee54c4a9a01f2cd94626.js:60:247452
value@https://graylog.local/assets/app.ee54c4a9a01f2cd94626.js:60:248629
Wi@https://graylog.local/assets/vendor.043dd426065882df527b.js:26:69874
Pi@https://graylog.local/assets/vendor.043dd426065882df527b.js:26:69669
Ms@https://graylog.local/assets/vendor.043dd426065882df527b.js:26:105468
uc@https://graylog.local/assets/vendor.043dd426065882df527b.js:26:96717
sc@https://graylog.local/assets/vendor.043dd426065882df527b.js:26:96640
Qs@https://graylog.local/assets/vendor.043dd426065882df527b.js:26:93670
Ko/<@https://graylog.local/assets/vendor.043dd426065882df527b.js:26:45312
29/exports.unstable_runWithPriority@https://graylog.local/assets/vendor.043dd426065882df527b.js:42:3988
Xo@https://graylog.local/assets/vendor.043dd426065882df527b.js:26:45021
Ko@https://graylog.local/assets/vendor.043dd426065882df527b.js:26:45259
Uo@https://graylog.local/assets/vendor.043dd426065882df527b.js:26:45192
Gs@https://graylog.local/assets/vendor.043dd426065882df527b.js:26:90455
enqueueSetState@https://graylog.local/assets/vendor.043dd426065882df527b.js:26:48977
24/y.prototype.setState@https://graylog.local/assets/vendor.043dd426065882df527b.js:34:1296
g/y</n.prototype.safeSetState@https://graylog.local/assets/app.ee54c4a9a01f2cd94626.js:53:146046
n/r.loadingPromise<@https://graylog.local/assets/app.ee54c4a9a01f2cd94626.js:53:145479
Component Stack:
in ConnectStoresWrapper[Provider] stores=view,configs
in Wu
in ConnectStoresWrapper[Wu] stores=view
in as
in withRouter(as)
in Unknown
in n
in c
in withRouter(c)
in Unknown
in n
in Unknown
in n
in div
in c
in div
in wt
in o
in Unknown
in withRouter(Component)
in d
in mt
in ConnectStoresWrapper[mt] stores=currentUser
in c
in RouterContext
in Router
in ar
in lr
in Unknown
in n
in Y
in ConnectStoresWrapper[Y] stores=currentUser,server,sessionId
in t
in p
Same here, using Graylog 3.3.5 and Elasticsearch 6.8.9 (both running in Docker).
Stacktrace
n is undefined
Stack Trace:
osx3epUg/os<@https://graylog.example.com/assets/ExtendedSearchPage.1ec71fc30880f2142b45.js:1:174393
m/<@https://graylog.example.com/assets/app.1ec71fc30880f2142b45.js:60:247452
value@https://graylog.example.com/assets/app.1ec71fc30880f2142b45.js:60:248629
Wi@https://graylog.example.com/assets/vendor.043dd426065882df527b.js:26:69874
Pi@https://graylog.example.com/assets/vendor.043dd426065882df527b.js:26:69669
Ms@https://graylog.example.com/assets/vendor.043dd426065882df527b.js:26:105468
uc@https://graylog.example.com/assets/vendor.043dd426065882df527b.js:26:96717
sc@https://graylog.example.com/assets/vendor.043dd426065882df527b.js:26:96640
Qs@https://graylog.example.com/assets/vendor.043dd426065882df527b.js:26:93670
Ko/<@https://graylog.example.com/assets/vendor.043dd426065882df527b.js:26:45312
29/exports.unstable_runWithPriority@https://graylog.example.com/assets/vendor.043dd426065882df527b.js:42:3988
Xo@https://graylog.example.com/assets/vendor.043dd426065882df527b.js:26:45021
Ko@https://graylog.example.com/assets/vendor.043dd426065882df527b.js:26:45259
Uo@https://graylog.example.com/assets/vendor.043dd426065882df527b.js:26:45192
Gs@https://graylog.example.com/assets/vendor.043dd426065882df527b.js:26:90455
enqueueSetState@https://graylog.example.com/assets/vendor.043dd426065882df527b.js:26:48977
24/y.prototype.setState@https://graylog.example.com/assets/vendor.043dd426065882df527b.js:34:1296
c/</<@https://graylog.example.com/assets/NewSearchPage.1ec71fc30880f2142b45.js:1:5888
Component Stack:
in ConnectStoresWrapper[Provider] stores=view,configs
in Wu
in ConnectStoresWrapper[Wu] stores=view
in as
in withRouter(as)
in Unknown
in n
in c
in withRouter(c)
in Unknown
in n
in Unknown
in n
in div
in c
in div
in wt
in o
in Unknown
in withRouter(Component)
in d
in ft
in ConnectStoresWrapper[ft] stores=currentUser
in c
in RouterContext
in Router
in ra
in la
in Unknown
in n
in Y
in ConnectStoresWrapper[Y] stores=currentUser,server,sessionId
in t
in p
Yesterday, the search did work, and I've not updated the container images in the meantime.
Addendum: The error happened directly after logging in. Closing and reopening the tab made the error disappear. Logging out and back in again did not reproduce the error.
Same versions ...
TypeError: e[n] is undefined
render BufferUsage.jsx:70
Wi vendor.043dd426065882df527b.js:26
Pi vendor.043dd426065882df527b.js:26
Ms vendor.043dd426065882df527b.js:26
uc vendor.043dd426065882df527b.js:26
sc vendor.043dd426065882df527b.js:26
Qs vendor.043dd426065882df527b.js:26
Ko vendor.043dd426065882df527b.js:26
unstable_runWithPriority vendor.043dd426065882df527b.js:42
Xo vendor.043dd426065882df527b.js:26
Ko vendor.043dd426065882df527b.js:26
Uo vendor.043dd426065882df527b.js:26
Gs vendor.043dd426065882df527b.js:26
enqueueSetState vendor.043dd426065882df527b.js:26
setState vendor.043dd426065882df527b.js:34
n vendor.043dd426065882df527b.js:18
emit vendor.043dd426065882df527b.js:133
trigger vendor.043dd426065882df527b.js:18
list MetricsStore.js:147
c bluebird.js:5370
_settlePromiseFromHandler bluebird.js:3366
_settlePromise bluebird.js:3423
_settlePromise0 bluebird.js:3468
_settlePromises bluebird.js:3548
u bluebird.js:145
s bluebird.js:138
_drainQueues bluebird.js:154
drainQueues bluebird.js:67
promise callback*o bluebird.js:4593
_queueTick bluebird.js:163
settlePromises bluebird.js:128
_fulfill bluebird.js:3494
_resolveCallback bluebird.js:3285
r bluebird.js:3338
promise index.js:97
callback client.js:645
m client.js:465
emit index.js:145
onreadystatechange client.js:761
_end client.js:735
end client.js:711
promise index.js:80
I bluebird.js:1033
_resolveFromExecutor bluebird.js:3337
I bluebird.js:2922
promise index.js:79
then index.js:121
value FetchProvider.js:92
U FetchProvider.js:183
U FetchProvider.js:186
list MetricsStore.js:141
n vendor.043dd426065882df527b.js:18
emit vendor.043dd426065882df527b.js:133
trigger vendor.043dd426065882df527b.js:18
triggerAsync vendor.043dd426065882df527b.js:18
exports _invoke.js:5
<anonymous> _task.js:35
d _task.js:21
P _task.js:25
GuUTRImU _task.js:57
Webpack 13
vendor.043dd426065882df527b.js:26:82383
We have experienced similar issue with GrayLog latest 3.3.8, ES 6.8.7, Mongo 3.6.3, Ubuntu 1804 - Web client Firefox 81.0.2, Windows 10 2004
n is undefined
Stack Trace:
osx3epUg/es<@http://graylog:9000/assets/ExtendedSearchPage.4678e54c30f1075e4dd8.js:1:172840
m/<@http://graylog:9000/assets/app.4678e54c30f1075e4dd8.js:60:247452
value@http://graylog:9000/assets/app.4678e54c30f1075e4dd8.js:60:248629
Wi@http://graylog:9000/assets/vendor.8d6aa5835c8302c41e2f.js:26:69874
Pi@http://graylog:9000/assets/vendor.8d6aa5835c8302c41e2f.js:26:69669
Ms@http://graylog:9000/assets/vendor.8d6aa5835c8302c41e2f.js:26:105468
uc@http://graylog:9000/assets/vendor.8d6aa5835c8302c41e2f.js:26:96717
sc@http://graylog:9000/assets/vendor.8d6aa5835c8302c41e2f.js:26:96640
Qs@http://graylog:9000/assets/vendor.8d6aa5835c8302c41e2f.js:26:93670
Ko/<@http://graylog:9000/assets/vendor.8d6aa5835c8302c41e2f.js:26:45312
29/exports.unstable_runWithPriority@http://graylog:9000/assets/vendor.8d6aa5835c8302c41e2f.js:42:3988
Xo@http://graylog:9000/assets/vendor.8d6aa5835c8302c41e2f.js:26:45021
Ko@http://graylog:9000/assets/vendor.8d6aa5835c8302c41e2f.js:26:45259
Uo@http://graylog:9000/assets/vendor.8d6aa5835c8302c41e2f.js:26:45192
Gs@http://graylog:9000/assets/vendor.8d6aa5835c8302c41e2f.js:26:90455
enqueueSetState@http://graylog:9000/assets/vendor.8d6aa5835c8302c41e2f.js:26:48977
24/y.prototype.setState@http://graylog:9000/assets/vendor.8d6aa5835c8302c41e2f.js:34:1296
c/<@http://graylog:9000/assets/NewSearchPage.4678e54c30f1075e4dd8.js:1:6354
Component Stack:
in ConnectStoresWrapper[Provider] stores=view,configs
in Au
in ConnectStoresWrapper[Au] stores=view
in ts
in withRouter(ts)
in Unknown
in n
in g
in c
in withRouter(c)
in Unknown
in n
in Unknown
in n
in div
in c
in div
in wt
in o
in Unknown
in withRouter(Component)
in d
in mt
in ConnectStoresWrapper[mt] stores=currentUser
in i
in RouterContext
in Router
in ar
in Unknown
in ConnectStoresWrapper[Unknown/Anonymous] stores=streams
in lr
in Unknown
in n
in Y
in ConnectStoresWrapper[Y] stores=currentUser,server,sessionId
in t
in p
Most helpful comment
Same here, using Graylog 3.3.5 and Elasticsearch 6.8.9 (both running in Docker).
Stacktrace
Yesterday, the search did work, and I've not updated the container images in the meantime.
Addendum: The error happened directly after logging in. Closing and reopening the tab made the error disappear. Logging out and back in again did not reproduce the error.