# Strange folder bug

**URL:** <https://discourse.slicer.org/t/strange-folder-bug/46835>\
**Category:** Support\
**Created:** [April 25, 2026, 11:12pm UTC](https://discourse.slicer.org/t/strange-folder-bug/46835 "2026-04-25T23:12:07Z")\
**Posts on this page:** 4\
**Page:** 1

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**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:** [April 25, 2026, 11:12pm UTC](https://discourse.slicer.org/t/strange-folder-bug/46835/1 "2026-04-25T23:12:07Z")

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In the latest preview in Macos, data module is behaving strangely:

1. Load two models in a blank scene
2. Create a NewFolder
3. Put the models in the NewFolder
4. Hit the visibility icon at the NewFolder and notice that those two models are now moved out of the NewFolder (they are at the same level, not nested in).

Subsequent ones (newfolders) do not show this behavior. They work correctly. This is vanilla slicer.

@lassoan @Sunderlandkyl @cpinter

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**Author:** ![mikebind](https://avatars.discourse-cdn.com/v4/letter/m/71e660/32.png) [@mikebind](https://discourse.slicer.org/u/mikebind)\
**Post date:** [April 27, 2026, 2:01am UTC](https://discourse.slicer.org/t/strange-folder-bug/46835/2 "2026-04-27T02:01:55Z")

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I have noticed odd bugs like this in subject hierarchy for a long time (I think since at least 5.6), but I never successfully came up with a reproducible series of actions which triggered incorrect behavior. Thanks for reporting and finding a reproducible way to trigger. Hopefully this will help lead to a solution!

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**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:** [April 27, 2026, 4:52am UTC](https://discourse.slicer.org/t/strange-folder-bug/46835/3 "2026-04-27T04:52:20Z")

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yeah there are more than one. For example,

Opacity slider is not visible the first time. it becomes visible after you toggle the visibility:

 ![image](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/f/a/fa4cbaf27dd0edc80f2d1d98f5e4f9b531ec30f7.png)

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**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 7, 2026, 11:14am UTC](https://discourse.slicer.org/t/strange-folder-bug/46835/4 "2026-05-07T11:14:40Z")

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Reference to the GitHub issue, where this conversation will be continued

> <https://github.com/Slicer/Slicer/issues/9130>
>
> as reported on the forum: https://discourse.slicer.org/t/strange-folder-bug/4683…5/3
> 
> \### issue1: losing hierarchy:
> In the latest preview in Macos, data module is behaving strangely:
> 
> Load two models in a blank scene
> Create a NewFolder
> Put the models in the NewFolder
> Hit the visibility icon at the NewFolder and notice that those two models are now moved out of the NewFolder (they are at the same level, not nested in).
> 
> Subsequent ones (newfolders) do not show this behavior. They work correctly. This is vanilla slicer.
> 
> \### issue2: Missing opacity slider
> 
> 1. Create a segmentation (with couple items in it)
> 2. Convert to model reprsentation using the right click in Data module.
> 3. Right click the visibility (eye) icon for the Model folder and notice that opacity slider is not there. 
> 4. Toggle the folder visibility on/off and see that opacity slider comes back.