# Extensions not showing anything

**URL:** <https://discourse.slicer.org/t/extensions-not-showing-anything/23432>\
**Category:** Support\
**Tags:** extensions-manager\
**Created:** [May 14, 2022, 7:36pm UTC](https://discourse.slicer.org/t/extensions-not-showing-anything/23432 "2022-05-14T19:36:05Z")\
**Posts on this page:** 8\
**Page:** 1

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**Author:** ![sodium83](https://avatars.discourse-cdn.com/v4/letter/s/ac91a4/32.png) [@sodium83](https://discourse.slicer.org/u/sodium83)\
**Post date:** [May 14, 2022, 7:36pm UTC](https://discourse.slicer.org/t/extensions-not-showing-anything/23432/1 "2022-05-14T19:36:05Z")

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Using Ubuntu 22.04 and Slicer 4.11.20210226. Also tried on the preview release.

Loading Extensions Manager shows 100% at bottom but nothing appears. I am just using this on a home computer with no firewalls etc. My internet connection otherwise works fine.

Desperately trying to install the VMTK.

Any help appreciated.

Kind regards,

Jeremy.

LOG:  
[DEBUG][Qt] 14.05.2022 09:33:30 [] (unknown:0) - Session start time …: 2022-05-14 09:33:30  
[DEBUG][Qt] 14.05.2022 09:33:30 [] (unknown:0) - Slicer version …: 4.11.20210226 (revision 29738 / 7a593c8) linux-amd64 - installed release  
[DEBUG][Qt] 14.05.2022 09:33:30 [] (unknown:0) - Operating system …: Linux / 5.15.0-27-generic / #28-Ubuntu SMP Thu Apr 14 04:55:28 UTC 2022 / UTF-8 - 64-bit  
[DEBUG][Qt] 14.05.2022 09:33:30 [] (unknown:0) - Memory …: 15788 MB physical, 2047 MB virtual  
[DEBUG][Qt] 14.05.2022 09:33:30 [] (unknown:0) - CPU …: GenuineIntel 12th Gen Intel(R) Core™ i5-12600K, 10 cores, 16 logical processors  
[DEBUG][Qt] 14.05.2022 09:33:30 [] (unknown:0) - VTK configuration …: OpenGL2 rendering, Sequential threading  
[DEBUG][Qt] 14.05.2022 09:33:30 [] (unknown:0) - Qt configuration …: version 5.15.1, with SSL, requested OpenGL 3.2 (core profile)  
[DEBUG][Qt] 14.05.2022 09:33:30 [] (unknown:0) - Developer mode enabled …: no  
[DEBUG][Qt] 14.05.2022 09:33:30 [] (unknown:0) - Prefer executable CLI …: yes  
[DEBUG][Qt] 14.05.2022 09:33:30 [] (unknown:0) - Application path …: /home/jeremy/.var/app/Slicer/bin  
[DEBUG][Qt] 14.05.2022 09:33:30 [] (unknown:0) - Additional module paths …: (none)  
[DEBUG][Python] 14.05.2022 09:33:31 [Python] (/home/jeremy/.var/app/Slicer/lib/Python/lib/python3.6/site-packages/pydicom/datadict.py:432) - Reversing DICOM dictionary so can look up tag from a keyword…  
[DEBUG][Python] 14.05.2022 09:33:33 [Python] (/home/jeremy/.var/app/Slicer/lib/Slicer-4.11/qt-scripted-modules/SubjectHierarchyPlugins/AbstractScriptedSubjectHierarchyPlugin.py:36) - Scripted subject hierarchy plugin registered: Annotations  
[DEBUG][Python] 14.05.2022 09:33:33 [Python] (/home/jeremy/.var/app/Slicer/lib/Slicer-4.11/qt-scripted-modules/SubjectHierarchyPlugins/AbstractScriptedSubjectHierarchyPlugin.py:36) - Scripted subject hierarchy plugin registered: SegmentEditor  
[DEBUG][Python] 14.05.2022 09:33:33 [Python] (/home/jeremy/.var/app/Slicer/lib/Slicer-4.11/qt-scripted-modules/SubjectHierarchyPlugins/AbstractScriptedSubjectHierarchyPlugin.py:36) - Scripted subject hierarchy plugin registered: SegmentStatistics  
[DEBUG][Qt] 14.05.2022 09:33:33 [] (unknown:0) - Switch to module: “Welcome”  
[WARNING][Qt] 14.05.2022 09:33:34 [] (unknown:0) - An OpenGL Core Profile was requested, but it is not supported on the current platform. Falling back to a non-Core profile. Note that this might cause rendering issues.  
[WARNING][Qt] 14.05.2022 09:33:39 [] (unknown:0) - QXcbConnection: XCB error: 3 (BadWindow), sequence: 2096, resource id: 13383320, major code: 40 (TranslateCoords), minor code: 0  
[WARNING][Qt] 14.05.2022 09:34:28 [] (unknown:0) - QXcbConnection: XCB error: 3 (BadWindow), sequence: 4651, resource id: 13387921, major code: 40 (TranslateCoords), minor code: 0

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<div class="post-metadata">

**Author:** ![lassoan](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/lassoan/32/13_2.png) [@lassoan](https://discourse.slicer.org/u/lassoan)\
**Post date:** [May 14, 2022, 9:04pm UTC](https://discourse.slicer.org/t/extensions-not-showing-anything/23432/2 "2022-05-14T21:04:56Z")

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Check out these troubleshooting instructions and let us know if they help:

[https://slicer.readthedocs.io/en/latest/user\_guide/extensions\_manager.html#extensions-manager-does-not-show-any-extensions](https://slicer.readthedocs.io/en/latest/user_guide/extensions_manager.html#extensions-manager-does-not-show-any-extensions)

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**Author:** ![Davide\_Cester](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/davide_cester/32/6564_2.png) [@Davide\_Cester](https://discourse.slicer.org/u/Davide_Cester)\
**Post date:** [May 17, 2022, 10:17am UTC](https://discourse.slicer.org/t/extensions-not-showing-anything/23432/3 "2022-05-17T10:17:42Z")

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Hi,

I am having a similar issue. The Extension list only reports “All (0)”. This happens both via Slicer and by manually visiting the URL [@KitwareMedical/slicer-extensions-webapp](http://slicer.kitware.com/midas3/slicerappstore)

EDIT: Slicer version 4.11.0-2020-06-12 r29143 / 95c7682  
I am using Ubuntu, my kernel is recent (5.13), the file ‘/proc/sys/kernel/unprivileged\_userns\_clone’ contains 1 and --no-sandbox has no effect, as well as QTWEBENGINE\_DISABLE\_SANDBOX=1 ./Slicer.

Any hint? 🙂

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<div class="post-metadata">

**Author:** ![cpinter](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/cpinter/32/7995_2.png) [@cpinter](https://discourse.slicer.org/u/cpinter)\
**Post date:** [May 17, 2022, 10:39am UTC](https://discourse.slicer.org/t/extensions-not-showing-anything/23432/4 "2022-05-17T10:39:16Z")

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The Midas backend of the older Slicer versions has been replaced by a new one, and so extensions for those versions are not available.

You’ll need to use a more recent Slicer. 5.0 will be released imminently, and the 5.1 preview version is virtually identical to the coming stable.

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<div class="post-metadata">

**Author:** ![RyanZurrin](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/ryanzurrin/32/15735_2.png) [@RyanZurrin](https://discourse.slicer.org/u/RyanZurrin)\
**Post date:** [September 12, 2022, 6:01pm UTC](https://discourse.slicer.org/t/extensions-not-showing-anything/23432/5 "2022-09-12T18:01:43Z")

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I am using Ubuntu 22.04 and was having the same issue.  
This is the step that worked for me, using this flag before launching Slicer: `QTWEBENGINE_DISABLE_SANDBOX=1`.

Thanks for pointing me in the right direction.

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**Author:** ![Gonzalo\_Rojas\_Costa](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/gonzalo_rojas_costa/32/5259_2.png) [@Gonzalo\_Rojas\_Costa](https://discourse.slicer.org/u/Gonzalo_Rojas_Costa)\
**Post date:** [January 19, 2023, 8:28pm UTC](https://discourse.slicer.org/t/extensions-not-showing-anything/23432/6 "2023-01-19T20:28:05Z")

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Where should I put `QTWEBENGINE_DISABLE_SANDBOX=1` ?

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<div class="post-metadata">

**Author:** ![muratmaga](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/muratmaga/32/3622_2.png) [@muratmaga](https://discourse.slicer.org/u/muratmaga)\
**Post date:** [January 19, 2023, 8:32pm UTC](https://discourse.slicer.org/t/extensions-not-showing-anything/23432/7 "2023-01-19T20:32:33Z")

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in the terminal window, before you start Slicer. So this will be shell command like  
`export QTWEBENGINE_DISABLE_SANDBOX=1`  
then you can invoke  
./Slicer  
and extension manager should be available to you.

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<div class="post-metadata">

**Author:** ![RafaelPalomar](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/rafaelpalomar/32/1436_2.png) [@RafaelPalomar](https://discourse.slicer.org/u/RafaelPalomar)\
**Post date:** [January 20, 2023, 5:49am UTC](https://discourse.slicer.org/t/extensions-not-showing-anything/23432/8 "2023-01-20T05:49:22Z")

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This issue was recently addressed ([BUG: Fix blank Extensions manager for Linux package due to Chromium sandboxing by jcfr · Pull Request #6744 · Slicer/Slicer · GitHub](https://github.com/Slicer/Slicer/pull/6744#event-8096626953)). In the current preview release there is no need to set this variable.