### Author:  [@DeanMarkTaylor](https://meta.discourse.org/u/DeanMarkTaylor)
#### Post date: [December 13, 2015, 11:18am UTC](https://meta.discourse.org/t/blank-page-javascript-error-on-android/36642/1 "2015-12-13T11:18:11Z")
##Info
Uncaught TypeError: Cannot read property ‘user’ of undefined
Url: [http://example.com/assets/application-622c68bf359d79a9bf2cb12ba4772774.js](http://example.com/assets/application-622c68bf359d79a9bf2cb12ba4772774.js)
Line: 3
Column: 30623
Window Location: [http://example.com/](http://example.com/)
##Backtrace
```
TypeError: Cannot read property 'user' of undefined
at p.extend.s.value (http://example.com/assets/application-622c68bf359d79a9bf2cb12ba4772774.js:3:30623)
at null. (http://example.com/assets/application-622c68bf359d79a9bf2cb12ba4772774.js:1:5924)
at a.d.get (http://example.com/assets/ember_jquery-c510009d3d7cecdf3f948f54d4922d9a.js:6:25589)
at s (http://example.com/assets/ember_jquery-c510009d3d7cecdf3f948f54d4922d9a.js:7:30860)
at l (http://example.com/assets/ember_jquery-c510009d3d7cecdf3f948f54d4922d9a.js:7:31452)
at Object.s [as get] (http://example.com/assets/ember_jquery-c510009d3d7cecdf3f948f54d4922d9a.js:7:30849)
at t.get (http://example.com/assets/application-622c68bf359d79a9bf2cb12ba4772774.js:1:20436)
at n (http://example.com/assets/application-622c68bf359d79a9bf2cb12ba4772774.js:1:18524)
at Object.Ember.TEMPLATES.mobile/list/topic_list_item.raw.Discourse.EmberCompatHandlebars.template.1 (http://example.com/assets/application-622c68bf359d79a9bf2cb12ba4772774.js:38:16392)
at Object.o [as inverse] (http://example.com/assets/vendor-2ff9e230f5bc60c6d19b98f79e81c3d5.js:1:8834)
```
##Env
`application_version 3c3d7c03f0cad4067988fce6e6e776a163875ff1`
##Repeatable in Chrome Dev Tools
---
### Author:  [@codinghorror](https://meta.discourse.org/u/codinghorror)
#### Post date: [December 13, 2015, 12:09pm UTC](https://meta.discourse.org/t/blank-page-javascript-error-on-android/36642/2 "2015-12-13T12:09:15Z")
You can repro this here on meta?
---
### Author:  [@DeanMarkTaylor](https://meta.discourse.org/u/DeanMarkTaylor)
#### Post date: [December 13, 2015, 6:14pm UTC](https://meta.discourse.org/t/blank-page-javascript-error-on-android/36642/3 "2015-12-13T18:14:07Z")
No, it looks data specific in that way. I have no additional plug ins and no customisations enabled.
---
### Author:  [@DeanMarkTaylor](https://meta.discourse.org/u/DeanMarkTaylor)
#### Post date: [December 13, 2015, 7:41pm UTC](https://meta.discourse.org/t/blank-page-javascript-error-on-android/36642/4 "2015-12-13T19:41:09Z")
Debugging this still further it looks like the `extras` data is empty for all users
At this point `t` is undefined after executing the `.filter` - so I dumped the data in `e` using `JSON.stringify(e)`:
```plaintext
[{
"extras": null,
"description": "Original Poster",
"user_id": 10309,
"user": {
"id": 10309,
"username": "andybarb",
"avatar_template": "/user_avatar/example.com/andybarb/{size}/24058_1.png",
"store": {}
}
}, {
"extras": null,
"description": "Frequent Poster",
"user_id": 651,
"user": {
"id": 651,
"username": "CDMH",
"avatar_template": "/user_avatar/example.com/cdmh/{size}/25343_1.png",
"store": {}
}
}, {
"extras": null,
"description": "Frequent Poster",
"user_id": 20,
"user": {
"id": 20,
"username": "Martyn",
"avatar_template": "/user_avatar/example.com/martyn/{size}/22504_1.png",
"store": {}
}
}, {
"extras": null,
"description": "Frequent Poster",
"user_id": 10155,
"user": {
"id": 10155,
"username": "maxxbradley",
"avatar_template": "/user_avatar/example.com/maxxbradley/{size}/21606_1.png",
"store": {}
}
}, {
"extras": null,
"description": "Frequent Poster",
"user_id": 9929,
"user": {
"id": 9929,
"username": "mark0",
"avatar_template": "/letter_avatar_proxy/v2/letter/m/8e7dd6/{size}.png",
"store": {}
}
}]
```
* * *
##Edit - Possible Cause
I believe the cause to be a change in ownership of the last post on a topic which is listed on the forum’s latest topics.
### (Hopefully) Steps to Reproduce
- Have two existing test Users - “User 1” and “User 2”
- Take an topic with several posts
- the topic that caused the issue had 22 posts (inc. topic post) - created by users other than “User 1” and “User 2”
- Make a new post in thread using “User 1”
- this post was made 5 months later
- Select the “User 1” post using the spanner and then using “Select Posts…”
- Select “change ownership” from the menu which just appeared.
- Change the owner user from “User 1” to “User 2”
- Delete “User 1”.
##Expected Result
- Forum to still load on Android and Desktop browsers alike.
##Actual Result
- White / Blank screen when loaded on Android.
- Loads and works correctly on Desktop Chrome browser.
---
### Author:  [@codinghorror](https://meta.discourse.org/u/codinghorror)
#### Post date: [December 13, 2015, 9:22pm UTC](https://meta.discourse.org/t/blank-page-javascript-error-on-android/36642/5 "2015-12-13T21:22:31Z")
Excellent repro see if you can also repro and correct this @techapj?
---
### Author:  [@sam](https://meta.discourse.org/u/sam)
#### Post date: [December 13, 2015, 9:27pm UTC](https://meta.discourse.org/t/blank-page-javascript-error-on-android/36642/6 "2015-12-13T21:27:38Z")
Note, this is not an android bug,it’s a mobile Bug
---
### Author:  [@sam](https://meta.discourse.org/u/sam)
#### Post date: [December 14, 2015, 5:25am UTC](https://meta.discourse.org/t/blank-page-javascript-error-on-android/36642/7 "2015-12-14T05:25:44Z")
This happens cause somehow we have a topic that has no latest poster.
I do not thing the client should crash out so I fixed that:
[https://github.com/discourse/discourse/commit/1ff5ed4e084b73d9b7e1ed4a1a624282a9970a12](https://github.com/discourse/discourse/commit/1ff5ed4e084b73d9b7e1ed4a1a624282a9970a12)
We should also clean up the “cast of characters” better in the case of user removals.
The bug in the OP is fixed
---
### Author:  [@zogstrip](https://meta.discourse.org/u/zogstrip)
#### Post date: [December 14, 2015, 3:05pm UTC](https://meta.discourse.org/t/blank-page-javascript-error-on-android/36642/8 "2015-12-14T15:05:52Z")
This topic was automatically closed after 6 hours. New replies are no longer allowed.