# Development

**URL:** https://discourse.slicer.org/c/dev/5.md?no_subcategories=false&page=5

[Latest](https://discourse.slicer.org/latest.md) · [Categories](https://discourse.slicer.org/categories.md) · [Tags](https://discourse.slicer.org/tags.md)

**Page:** 6

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## [Seeking Tips for Slicer Python Autocompletion and Debugging in VS Code](https://discourse.slicer.org/t/seeking-tips-for-slicer-python-autocompletion-and-debugging-in-vs-code/43751)

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**Author:** [@tas47](https://discourse.slicer.org/u/tas47)\
**Replies:** 3\
**Last updated:** [August 26, 2025, 10:28pm UTC](https://discourse.slicer.org/t/seeking-tips-for-slicer-python-autocompletion-and-debugging-in-vs-code/43751 "2025-08-26T22:28:20Z")

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Hello all, I wanted to revisit a discussion about auto completes to work on Slicer source code. I find myself always reading the source code to map many of the C++ code to python wrappers and etc. I visited this issu…

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## [Maintenance of Windows dashboard planned for August 26th](https://discourse.slicer.org/t/maintenance-of-windows-dashboard-planned-for-august-26th/44210)

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**Author:** [@jcfr](https://discourse.slicer.org/u/jcfr)\
**Replies:** 3\
**Last updated:** [August 26, 2025, 9:06pm UTC](https://discourse.slicer.org/t/maintenance-of-windows-dashboard-planned-for-august-26th/44210 "2025-08-26T21:06:28Z")

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The Windows dashboard server (bluestreak) will be temporarily unavailable this afternoon for a scheduled system upgrade by the Kitware team. We expect the system to be back online later this evening. However, please not…

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## [Third party shared LIB file placement in a custom Slicer application](https://discourse.slicer.org/t/third-party-shared-lib-file-placement-in-a-custom-slicer-application/44203)

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**Author:** [@ejm-revvity](https://discourse.slicer.org/u/ejm-revvity)\
**Replies:** 0\
**Last updated:** [August 25, 2025, 9:16pm UTC](https://discourse.slicer.org/t/third-party-shared-lib-file-placement-in-a-custom-slicer-application/44203 "2025-08-25T21:16:27Z")

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I’m adding in license management functionality to our custom Slicer application. We’re using Revanera FlexNet which provides a sort of SDK in the form of include (.h) files, .lib files and runtime .dll files. I can succ…

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## [OpenDose3D Run Test error](https://discourse.slicer.org/t/opendose3d-run-test-error/44200)

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**Author:** [@gaia\_muti](https://discourse.slicer.org/u/gaia_muti)\
**Replies:** 1\
**Last updated:** [August 25, 2025, 6:50pm UTC](https://discourse.slicer.org/t/opendose3d-run-test-error/44200 "2025-08-25T18:50:37Z")

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Problem report for Slicer 5.6.2 win-amd64: \[please describe expected and actual behavior\] After installing Slicer 5.6.2 and the requested extension for OpenDose3D, after running the test to check the correct functioning…

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## [New extension: Synchronised Navigation with Registration](https://discourse.slicer.org/t/new-extension-synchronised-navigation-with-registration/43844)

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**Author:** [@koeglfryderyk](https://discourse.slicer.org/u/koeglfryderyk)\
**Replies:** 13\
**Last updated:** [August 25, 2025, 8:47am UTC](https://discourse.slicer.org/t/new-extension-synchronised-navigation-with-registration/43844 "2025-08-25T08:47:24Z")

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I created a new extension for viewing registrations. It implements what is sometimes called “synchronised navigation” - simultaneous visualization of the same spatial location across multiple image series The basic idea…

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## [3D rendering of segmentations without Slicer GUI](https://discourse.slicer.org/t/3d-rendering-of-segmentations-without-slicer-gui/44177)

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**Author:** [@metabot18](https://discourse.slicer.org/u/metabot18)\
**Replies:** 1\
**Last updated:** [August 23, 2025, 2:50pm UTC](https://discourse.slicer.org/t/3d-rendering-of-segmentations-without-slicer-gui/44177 "2025-08-23T14:50:35Z")

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Hello Slicer community. Is it possible to generate 3D renderings like these by calling Slicer’s functions from a Python environment, without having to load Slicer’s GUI? I tried doing these through VTK Python, but I…

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## [Read in Strings to vtkTableNode?](https://discourse.slicer.org/t/read-in-strings-to-vtktablenode/44171)

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**Author:** [@mrsh0r3s](https://discourse.slicer.org/u/mrsh0r3s)\
**Replies:** 1\
**Last updated:** [August 23, 2025, 2:57am UTC](https://discourse.slicer.org/t/read-in-strings-to-vtktablenode/44171 "2025-08-23T02:57:49Z")

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Hello, Whenever I try to use the slicer.util.updateTableFromArray() function to import an array with a string value - say “DeviceID” - I get the error “ValueError: could not convert string to float: ‘DeviceID’” Numeric…

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## [How to Optimize Slicer Extension Load Time for Large Custom Toolsets](https://discourse.slicer.org/t/how-to-optimize-slicer-extension-load-time-for-large-custom-toolsets/44091)

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**Author:** [@fopodon](https://discourse.slicer.org/u/fopodon)\
**Replies:** 1\
**Last updated:** [August 22, 2025, 9:45am UTC](https://discourse.slicer.org/t/how-to-optimize-slicer-extension-load-time-for-large-custom-toolsets/44091 "2025-08-22T09:45:09Z")

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Hello I am developing a custom Slicer extension that bundles many specialized tools & modules for a specific medical imaging workflow.:slightly\_smiling\_face: While the extension works well once loaded; the startup time…

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## [Can qSlicerSimpleMarkupsNodes edit MarkupsLineNodes?](https://discourse.slicer.org/t/can-qslicersimplemarkupsnodes-edit-markupslinenodes/44152)

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**Author:** [@mrsh0r3s](https://discourse.slicer.org/u/mrsh0r3s)\
**Replies:** 4\
**Last updated:** [August 20, 2025, 10:47pm UTC](https://discourse.slicer.org/t/can-qslicersimplemarkupsnodes-edit-markupslinenodes/44152 "2025-08-20T22:47:45Z")

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Hello, I am trying to centralize some steps in a workflow and thus want to add a markups widget to the extension. I tried a qSlicerSimpleMarkupsWidget but it only seems to interact with point list markupsnodes rather th…

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## [Where to put libraries needed for installation/import?](https://discourse.slicer.org/t/where-to-put-libraries-needed-for-installation-import/44092)

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**Author:** [@Canada101](https://discourse.slicer.org/u/Canada101)\
**Replies:** 1\
**Last updated:** [August 19, 2025, 6:17am UTC](https://discourse.slicer.org/t/where-to-put-libraries-needed-for-installation-import/44092 "2025-08-19T06:17:18Z")

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I am developing an extension and am in the very early phases. I see in the 3d slicer documentation that there is a superbuild extension template, does that whole template replace the CmakeLists file the extension creatio…

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## [Build error in Windows in debug mode due to python312\_d.lib](https://discourse.slicer.org/t/build-error-in-windows-in-debug-mode-due-to-python312-d-lib/43781)

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**Author:** [@lassoan](https://discourse.slicer.org/u/lassoan)\
**Replies:** 9\
**Last updated:** [August 18, 2025, 9:41am UTC](https://discourse.slicer.org/t/build-error-in-windows-in-debug-mode-due-to-python312-d-lib/43781 "2025-08-18T09:41:25Z")

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I’ve been building Slicer for a long while using the same scripts. I’ve updated to the latest Slicer main version (from a version maybe a few weeks ago), started a clean build from scratch (removed all build folders) and…

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## [Hiding nodes from qMRMLSubjectHierarchyTreeView widget](https://discourse.slicer.org/t/hiding-nodes-from-qmrmlsubjecthierarchytreeview-widget/44019)

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**Author:** [@Victor\_Wayne](https://discourse.slicer.org/u/Victor_Wayne)\
**Replies:** 3\
**Last updated:** [August 13, 2025, 8:51am UTC](https://discourse.slicer.org/t/hiding-nodes-from-qmrmlsubjecthierarchytreeview-widget/44019 "2025-08-13T08:51:58Z")

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Hello, I inspected the Data module and found out that it is using qMRMLSubjectHierarchyTreeView widget for showing the nodes in a tree view. I wanted to customize the Data module by creating my own custom widget. So I c…

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## [How to save slicer scene with both slicer data and with "self.variables" within custom widget](https://discourse.slicer.org/t/how-to-save-slicer-scene-with-both-slicer-data-and-with-self-variables-within-custom-widget/9830)

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**Author:** [@jdp](https://discourse.slicer.org/u/jdp)\
**Replies:** 19\
**Last updated:** [August 11, 2025, 9:06am UTC](https://discourse.slicer.org/t/how-to-save-slicer-scene-with-both-slicer-data-and-with-self-variables-within-custom-widget/9830 "2025-08-11T09:06:08Z")

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I am using Slicer to create a widget for an application in which I would like to save my work. I see in slicer there is saveScene() in which I can do an mrml or a mrb file - which I can get to work. However, the widget a…

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## [CDash build error: JSON not found](https://discourse.slicer.org/t/cdash-build-error-json-not-found/40241)

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**Author:** [@acsenrafilho](https://discourse.slicer.org/u/acsenrafilho)\
**Replies:** 6\
**Last updated:** [August 9, 2025, 9:40pm UTC](https://discourse.slicer.org/t/cdash-build-error-json-not-found/40241 "2025-08-09T21:40:22Z")

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Hi Slicers, I have uploaded some projects to the Slicer Extension Index. Some of them presented the following build error: error: EXTENSION\_FILE CMake variable points to a inexistent file or directory: /.../SlicerDTI…

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## [Can SlicerIGT Fiducial Registration Wizard use global coordinates instead of RAS?](https://discourse.slicer.org/t/can-slicerigt-fiducial-registration-wizard-use-global-coordinates-instead-of-ras/44007)

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**Author:** [@Noam\_Borenstein](https://discourse.slicer.org/u/Noam_Borenstein)\
**Replies:** 3\
**Last updated:** [August 8, 2025, 8:49pm UTC](https://discourse.slicer.org/t/can-slicerigt-fiducial-registration-wizard-use-global-coordinates-instead-of-ras/44007 "2025-08-08T20:49:28Z")

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Hi everyone! I am working with a tracked knee model using an NDI camera. I am trying to find the transform between two sets of moving point lists using the fiducial registration wizard. If I move a point in the local/RA…

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## [How to build only a loadable module](https://discourse.slicer.org/t/how-to-build-only-a-loadable-module/43996)

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**Author:** [@koeglfryderyk](https://discourse.slicer.org/u/koeglfryderyk)\
**Replies:** 1\
**Last updated:** [August 7, 2025, 2:34pm UTC](https://discourse.slicer.org/t/how-to-build-only-a-loadable-module/43996 "2025-08-07T14:34:37Z")

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I’m working on the Transforms loadable module on Ubuntu. Is there a way to only re-build this module without re-building all of Slicer?

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## [Adding nodes to qMRMLSubjectHierarchyTreeView](https://discourse.slicer.org/t/adding-nodes-to-qmrmlsubjecthierarchytreeview/43999)

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**Author:** [@Victor\_Wayne](https://discourse.slicer.org/u/Victor_Wayne)\
**Replies:** 0\
**Last updated:** [August 7, 2025, 12:36pm UTC](https://discourse.slicer.org/t/adding-nodes-to-qmrmlsubjecthierarchytreeview/43999 "2025-08-07T12:36:13Z")

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Hello, In my custom widget, I have added an empty qMRMLSubjectHierarchyTreeView. I have a class that tracks nodes of a plans. I just need to show those node inside the qMRMLSubjectHierarchyTreeView so that I can get the…

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## [Adding nodes in qMRMLSubjectHierarchyTreeView](https://discourse.slicer.org/t/adding-nodes-in-qmrmlsubjecthierarchytreeview/43993)

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**Author:** [@Victor\_Wayne](https://discourse.slicer.org/u/Victor_Wayne)\
**Replies:** 1\
**Last updated:** [August 7, 2025, 12:28pm UTC](https://discourse.slicer.org/t/adding-nodes-in-qmrmlsubjecthierarchytreeview/43993 "2025-08-07T12:28:23Z")

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Hello, I am tracking some line nodes of type \`vtkMRMLMarkupsLineNode\` in a class called Plan for specific plan created by the user. How can I add those lines to the qMRMLSubjectHierarchyTreeView that I created in my cu…

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## [How to add folder in scene?](https://discourse.slicer.org/t/how-to-add-folder-in-scene/29499)

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**Author:** [@dsa934](https://discourse.slicer.org/u/dsa934)\
**Replies:** 15\
**Last updated:** [August 7, 2025, 12:26pm UTC](https://discourse.slicer.org/t/how-to-add-folder-in-scene/29499 "2025-08-07T12:26:54Z")

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Operating system: window 10 Slicer version: 5.2.1 how can i do this in python code ? I want to know how to add a folder in the scene and add data to that folder. Or can I add a folder that I already have locally t…

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## [QLineEdit in extension UI: Cursor jumping to end of line (bug?)](https://discourse.slicer.org/t/qlineedit-in-extension-ui-cursor-jumping-to-end-of-line-bug/43954)

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**Author:** [@shai-ikko](https://discourse.slicer.org/u/shai-ikko)\
**Replies:** 6\
**Last updated:** [August 5, 2025, 4:42pm UTC](https://discourse.slicer.org/t/qlineedit-in-extension-ui-cursor-jumping-to-end-of-line-bug/43954 "2025-08-05T16:42:50Z")

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Hi, I’ve been writing some Slicer extensions using the Extension Wizard & Qt Designer, and it’s been mostly working very well. But I’m seeing a funny behavior, which I think is a bug. I have extensions which use simple…

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## [AttributeError: 'vtkSlicerMarkupsModuleMRMLPython.vtkMRMLMarkupsClo' object has no attribute 'GetImageData'](https://discourse.slicer.org/t/attributeerror-vtkslicermarkupsmodulemrmlpython-vtkmrmlmarkupsclo-object-has-no-attribute-getimagedata/43890)

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**Author:** [@Gruoss](https://discourse.slicer.org/u/Gruoss)\
**Replies:** 3\
**Last updated:** [August 5, 2025, 11:32am UTC](https://discourse.slicer.org/t/attributeerror-vtkslicermarkupsmodulemrmlpython-vtkmrmlmarkupsclo-object-has-no-attribute-getimagedata/43890 "2025-08-05T11:32:10Z")

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Hi, I’m new to Slicer (version 5.8.1 on Windows 11 Pro) and would like to calculate radiomics features from native 2D DICOM images. I’m trying this code in the Python-Slicer terminal: import slicer import numpy as np …

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## [Synchronization of Axial, Coronal, and Sagittal slices by clicking on a pixel from one of the views](https://discourse.slicer.org/t/synchronization-of-axial-coronal-and-sagittal-slices-by-clicking-on-a-pixel-from-one-of-the-views/43943)

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**Author:** [@shahrokh](https://discourse.slicer.org/u/shahrokh)\
**Replies:** 1\
**Last updated:** [August 4, 2025, 6:24pm UTC](https://discourse.slicer.org/t/synchronization-of-axial-coronal-and-sagittal-slices-by-clicking-on-a-pixel-from-one-of-the-views/43943 "2025-08-04T18:24:40Z")

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Hello Dear Developers and Users To draw ROI, it is needed that three views axial, coronal, and sagittal be synchronize together. This means, for example, by clicking on one certain pixel in sagittal slice, the slices sh…

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## [Unexpected behaviour with torch.jit.load](https://discourse.slicer.org/t/unexpected-behaviour-with-torch-jit-load/42685)

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**Author:** [@ciro.raggio](https://discourse.slicer.org/u/ciro.raggio)\
**Replies:** 2\
**Last updated:** [July 31, 2025, 9:38am UTC](https://discourse.slicer.org/t/unexpected-behaviour-with-torch-jit-load/42685 "2025-07-31T09:38:43Z")

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Hi everyone! I’m trying to use a custom pre-trained torch model in a scripted module, but I encountered a problem that I couldn’t fix. Following the guide “Deploying your MONAI machine learning model within 3D Slicer”, …

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## [Combining multiple segments by name (python)](https://discourse.slicer.org/t/combining-multiple-segments-by-name-python/36331)

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**Author:** [@rkraaijveld](https://discourse.slicer.org/u/rkraaijveld)\
**Replies:** 6\
**Last updated:** [July 28, 2025, 1:47pm UTC](https://discourse.slicer.org/t/combining-multiple-segments-by-name-python/36331 "2025-07-28T13:47:42Z")

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Hi! Whenever I have my segmentations for several organs, such as Liver, Lungs, Kidney, I tend to split them into the connected components. I want to make an additional button in the Segment Editor where after splitting …

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## [Streaming Red Slice to mobile device](https://discourse.slicer.org/t/streaming-red-slice-to-mobile-device/10927)

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**Author:** [@mcfly3001](https://discourse.slicer.org/u/mcfly3001)\
**Replies:** 21\
**Last updated:** [October 13, 2021, 6:36pm UTC](https://discourse.slicer.org/t/streaming-red-slice-to-mobile-device/10927 "2021-10-13T18:36:30Z")

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Hi, I am currently trying to find out how I could stream one of Slicers slices (e.g. the red slice) to another device. There seem to be lots of options to receive image streams in Slicer (e.g. PlusToolkit, OpenIGTLink) …

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## [Transformed ROI shows up as changed in Save dialog directly after opening an mrml scene](https://discourse.slicer.org/t/transformed-roi-shows-up-as-changed-in-save-dialog-directly-after-opening-an-mrml-scene/43384)

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**Author:** [@MMMPPPMMM](https://discourse.slicer.org/u/MMMPPPMMM)\
**Replies:** 3\
**Last updated:** [July 27, 2025, 10:13am UTC](https://discourse.slicer.org/t/transformed-roi-shows-up-as-changed-in-save-dialog-directly-after-opening-an-mrml-scene/43384 "2025-07-27T10:13:41Z")

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Hello I think it is a bug that a transformed ROI shows up as changed in Save dialog directly after opening an MRML scene? Find an example here: Download Transformed\_ROI\_Test.zip | LimeWire Tested with Slicer 5.8.1 …

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## [Not able to load Freesurfer Model (lh.pial) on Slicer 5.8.1](https://discourse.slicer.org/t/not-able-to-load-freesurfer-model-lh-pial-on-slicer-5-8-1/43761)

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**Author:** [@justomont](https://discourse.slicer.org/u/justomont)\
**Replies:** 4\
**Last updated:** [July 22, 2025, 9:31am UTC](https://discourse.slicer.org/t/not-able-to-load-freesurfer-model-lh-pial-on-slicer-5-8-1/43761 "2025-07-22T09:31:30Z")

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I’m trying to load a FreeSurfer model (lh.pial) programmatically through a scripted module but I’m not achieving it. I’ve tried: fsImporterLogic = slicer.util.getModuleLogic('FreeSurferImporter') volumeNode = fsImporte…

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## [Maintenance of Linux dashboard planned for June 30th to July 1st](https://discourse.slicer.org/t/maintenance-of-linux-dashboard-planned-for-june-30th-to-july-1st/43462)

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**Author:** [@jcfr](https://discourse.slicer.org/u/jcfr)\
**Replies:** 5\
**Last updated:** [July 22, 2025, 5:34am UTC](https://discourse.slicer.org/t/maintenance-of-linux-dashboard-planned-for-june-30th-to-july-1st/43462 "2025-07-22T05:34:24Z")

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The Linux dashboard server (metroplex) will be temporarily unavailable from June 30 through July 1 due to a scheduled system upgrade by the Kitware team. As a result, the latest Preview Slicer application and extension …

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## [Is it possible to use closed curve node to cut segmentatin node or model node?](https://discourse.slicer.org/t/is-it-possible-to-use-closed-curve-node-to-cut-segmentatin-node-or-model-node/43785)

<div class="topic-metadata">

**Author:** [@jay1987](https://discourse.slicer.org/u/jay1987)\
**Replies:** 4\
**Last updated:** [July 20, 2025, 11:11pm UTC](https://discourse.slicer.org/t/is-it-possible-to-use-closed-curve-node-to-cut-segmentatin-node-or-model-node/43785 "2025-07-20T23:11:11Z")

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i have a closed curve node on a segmentation node , is it possible to use curved node to cut the segmentation node use script like the function of scissors?

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## [Way to create permanent slice intersection](https://discourse.slicer.org/t/way-to-create-permanent-slice-intersection/13284)

<div class="topic-metadata">

**Author:** [@Jakew](https://discourse.slicer.org/u/Jakew)\
**Replies:** 13\
**Last updated:** [July 16, 2025, 7:04am UTC](https://discourse.slicer.org/t/way-to-create-permanent-slice-intersection/13284 "2025-07-16T07:04:40Z")

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when slice intersection is enabled, the user can see a line that indicates where the slice they are currently viewing is relative to the other views. I was wondering if there was a way to create a static line for a certa…

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