Session restore: Unknown class name 'SceneAnimation'

[xfang93@…]

The following bug report has been submitted:
Platform:        macOS-15.7.5-arm64-arm-64bit
ChimeraX Version: 1.11.1 (2026-01-23 05:51:34 UTC)
Description
Replace this text with list of actions that caused this problem to occur

Log:
UCSF ChimeraX version: 1.11.1 (2026-01-23)  
© 2016-2025 Regents of the University of California. All rights reserved.  
How to cite UCSF ChimeraX  

> open
> /Users/fangxiang/Documents/HKU/Nilab/Flaviviruses/Zika/Manuscript/Supplement/S9/Ring_NS2B_TM.cxs

Opened Neck_5.16_relion_locres_filtered.mrc as #1, grid size 240,240,240,
pixel 1.57, shown at level 0.00251, step 1, values float32  
Opened Ring_3.67_M_ZIKV_denoised.mrc as #2, grid size 306,306,306, pixel 1.57,
shown at level 0.000505, step 1, values float32  
Opened Ring_3.67_M_ZIKV_denoised.mrc zone as #5, grid size 306,306,306, pixel
1.57, shown at level 0.000505, step 1, values float32  
Opened Ring_3.67_M_ZIKV_denoised.mrc zone as #6, grid size 306,306,306, pixel
1.57, shown at level 0.000505, step 1, values float32  
Unable to restore session, resetting.  
  
Traceback (most recent call last):  
File
"/Applications/ChimeraX-1.11.1.app/Contents/Library/Frameworks/Python.framework/Versions/3.11/lib/python3.11/site-
packages/chimerax/core/session.py", line 847, in restore  
cls = name.class_of(self)  
^^^^^^^^^^^^^^^^^^^  
File
"/Applications/ChimeraX-1.11.1.app/Contents/Library/Frameworks/Python.framework/Versions/3.11/lib/python3.11/site-
packages/chimerax/core/session.py", line 228, in class_of  
cls = bundle_info.get_class(class_name, session.logger)  
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^  
File
"/Applications/ChimeraX-1.11.1.app/Contents/Library/Frameworks/Python.framework/Versions/3.11/lib/python3.11/site-
packages/chimerax/core/toolshed/info.py", line 487, in get_class  
return f(class_name)  
^^^^^^^^^^^^^  
File
"/Applications/ChimeraX-1.11.1.app/Contents/Library/Frameworks/Python.framework/Versions/3.11/lib/python3.11/site-
packages/chimerax/animations/__init__.py", line 24, in get_class  
raise ValueError("Unknown class name '%s'" % class_name)  
ValueError: Unknown class name 'SceneAnimation'  
  

> view name session-start

opened ChimeraX session  




OpenGL version: 4.1 Metal - 89.4
OpenGL renderer: Apple M3 Pro
OpenGL vendor: Apple

Python: 3.11.9
Locale: en_US.UTF-8
Qt version: PyQt6 6.9.1, Qt 6.9.0
Qt runtime version: 6.9.2
Qt platform: cocoa
Hardware:

    Hardware Overview:

      Model Name: MacBook Pro
      Model Identifier: Mac15,6
      Model Number: MRX43ZP/A
      Chip: Apple M3 Pro
      Total Number of Cores: 12 (6 performance and 6 efficiency)
      Memory: 18 GB
      System Firmware Version: mBoot-18000.101.7
      OS Loader Version: 11881.140.96.701.1

Software:

    System Software Overview:

      System Version: macOS 15.7.5 (24G624)
      Kernel Version: Darwin 24.6.0
      Time since boot: 1 day, 16 hours, 18 minutes

Graphics/Displays:

    Apple M3 Pro:

      Chipset Model: Apple M3 Pro
      Type: GPU
      Bus: Built-In
      Total Number of Cores: 18
      Vendor: Apple (0x106b)
      Metal Support: Metal 3
      Displays:
        Color LCD:
          Display Type: Built-in Liquid Retina XDR Display
          Resolution: 3024 x 1964 Retina
          Main Display: Yes
          Mirror: Off
          Online: Yes
          Automatically Adjust Brightness: Yes
          Connection Type: Internal


Installed Packages:
    aiohappyeyeballs: 2.6.1
    aiohttp: 3.13.1
    aiosignal: 1.4.0
    alabaster: 1.0.0
    annotated-types: 0.7.0
    anyio: 4.12.1
    appdirs: 1.4.4
    appnope: 0.1.4
    asttokens: 3.0.1
    attrs: 25.4.0
    babel: 2.17.0
    beautifulsoup4: 4.13.5
    blockdiag: 3.0.0
    blosc2: 3.12.2
    build: 1.3.0
    certifi: 2025.7.14
    cftime: 1.6.5
    charset-normalizer: 3.4.4
    ChimeraX-AddCharge: 1.5.20
    ChimeraX-AddH: 2.2.8
    ChimeraX-AlignmentAlgorithms: 2.0.2
    ChimeraX-AlignmentHdrs: 3.6.1
    ChimeraX-AlignmentMatrices: 2.1
    ChimeraX-Alignments: 3.1.1
    ChimeraX-AlphaFold: 1.0.1
    ChimeraX-AltlocExplorer: 1.2
    ChimeraX-AmberInfo: 1.0
    ChimeraX-Animations: 1.0
    ChimeraX-Aniso: 1.3.2
    ChimeraX-Arrays: 1.1
    ChimeraX-ArtiaX: 0.6.0
    ChimeraX-Atomic: 1.61.4
    ChimeraX-AtomicLibrary: 14.2.1
    ChimeraX-AtomSearch: 2.0.1
    ChimeraX-AxesPlanes: 2.4
    ChimeraX-BasicActions: 1.1.3
    ChimeraX-BILD: 1.0
    ChimeraX-BlastProtein: 3.0.0
    ChimeraX-Boltz: 1.1
    ChimeraX-BondRot: 2.0.4
    ChimeraX-BugReporter: 1.0.2
    ChimeraX-BuildStructure: 2.13.1
    ChimeraX-Bumps: 1.0
    ChimeraX-BundleBuilder: 1.6.0
    ChimeraX-ButtonPanel: 1.0.1
    ChimeraX-CageBuilder: 1.0.1
    ChimeraX-CellPack: 1.0
    ChimeraX-Centroids: 1.4
    ChimeraX-ChangeChains: 1.1
    ChimeraX-CheckWaters: 1.5
    ChimeraX-ChemGroup: 2.0.2
    ChimeraX-Clashes: 2.3
    ChimeraX-Clipper: 0.26.1
    ChimeraX-ColorActions: 1.0.5
    ChimeraX-ColorGlobe: 1.0
    ChimeraX-ColorKey: 1.5.8
    ChimeraX-CommandLine: 1.3.0
    ChimeraX-ConnectStructure: 2.0.1
    ChimeraX-Contacts: 1.0.1
    ChimeraX-Core: 1.11.1
    ChimeraX-CoreFormats: 1.2
    ChimeraX-coulombic: 1.4.5
    ChimeraX-Crosslinks: 1.0
    ChimeraX-Crystal: 1.0
    ChimeraX-CrystalContacts: 1.0.1
    ChimeraX-DataFormats: 1.2.4
    ChimeraX-Dicom: 1.2.7
    ChimeraX-DistMonitor: 1.4.2
    ChimeraX-DockPrep: 1.1.4
    ChimeraX-Dssp: 2.0
    ChimeraX-EMDB-SFF: 1.0
    ChimeraX-ESMFold: 1.0
    ChimeraX-FileHistory: 1.0.1
    ChimeraX-FunctionKey: 1.0.1
    ChimeraX-Geometry: 1.3
    ChimeraX-gltf: 1.0
    ChimeraX-Graphics: 1.4.1
    ChimeraX-Hbonds: 2.5.3
    ChimeraX-Help: 1.3
    ChimeraX-HKCage: 1.3
    ChimeraX-IHM: 1.1
    ChimeraX-ImageFormats: 1.2
    ChimeraX-IMOD: 1.0
    ChimeraX-IO: 1.0.4
    ChimeraX-ISOLDE: 1.11.1
    ChimeraX-ItemsInspection: 1.0.1
    ChimeraX-IUPAC: 1.0
    ChimeraX-KVFinder: 1.7.3
    ChimeraX-Label: 1.2
    ChimeraX-ListInfo: 1.2.2
    ChimeraX-Log: 1.2.2
    ChimeraX-LookingGlass: 1.1
    ChimeraX-Maestro: 1.9.2
    ChimeraX-Map: 1.3
    ChimeraX-MapData: 2.0
    ChimeraX-MapEraser: 1.0.1
    ChimeraX-MapFilter: 2.0.1
    ChimeraX-MapFit: 2.0
    ChimeraX-MapSeries: 2.1.1
    ChimeraX-Markers: 1.0.1
    ChimeraX-Mask: 1.0.2
    ChimeraX-MatchMaker: 2.2.2
    ChimeraX-MCopy: 1.0
    ChimeraX-MCPServer: 0.1.0
    ChimeraX-MDcrds: 2.17.2
    ChimeraX-MedicalToolbar: 1.1
    ChimeraX-Meeting: 1.0.1
    ChimeraX-Minimize: 1.3.2
    ChimeraX-MLP: 1.1.1
    ChimeraX-mmCIF: 2.16
    ChimeraX-MMTF: 2.2
    ChimeraX-ModelArchive: 1.0
    ChimeraX-Modeller: 1.5.22
    ChimeraX-ModelPanel: 1.6
    ChimeraX-ModelSeries: 1.0.1
    ChimeraX-Mol2: 2.0.3
    ChimeraX-Mole: 1.0
    ChimeraX-Morph: 1.0.2
    ChimeraX-MouseModes: 1.2
    ChimeraX-Movie: 1.0.1
    ChimeraX-MutationScores: 1.0
    ChimeraX-Neuron: 1.0
    ChimeraX-Nifti: 1.2
    ChimeraX-NMRSTAR: 1.0.2
    ChimeraX-NRRD: 1.2
    ChimeraX-Nucleotides: 2.0.3
    ChimeraX-OpenCommand: 1.15.2
    ChimeraX-OrthoPick: 1.0.1
    ChimeraX-PDB: 2.7.12
    ChimeraX-PDBBio: 1.0.1
    ChimeraX-PDBLibrary: 1.0.5
    ChimeraX-PDBMatrices: 1.0
    ChimeraX-PhenixUI: 1.5.4
    ChimeraX-PickBlobs: 1.0.1
    ChimeraX-Positions: 1.0
    ChimeraX-PresetMgr: 1.1.4
    ChimeraX-ProfileGrids: 1.4.2
    ChimeraX-PubChem: 2.2
    ChimeraX-ReadPbonds: 1.0.1
    ChimeraX-Registration: 1.1.2
    ChimeraX-RemoteControl: 1.0
    ChimeraX-RenderByAttr: 1.6.5
    ChimeraX-RenumberResidues: 1.1
    ChimeraX-ResidueFit: 1.0.1
    ChimeraX-RestServer: 1.3.3
    ChimeraX-RNALayout: 1.0
    ChimeraX-RotamerLibMgr: 4.0
    ChimeraX-RotamerLibsDunbrack: 2.0
    ChimeraX-RotamerLibsDynameomics: 2.0
    ChimeraX-RotamerLibsRichardson: 2.0
    ChimeraX-SaveCommand: 1.5.2
    ChimeraX-Scenes: 0.3.1
    ChimeraX-SchemeMgr: 1.0
    ChimeraX-SDF: 2.0.3
    ChimeraX-Segger: 1.0
    ChimeraX-Segment: 1.0.1
    ChimeraX-Segmentations: 3.5.10
    ChimeraX-SelInspector: 1.0
    ChimeraX-SeqView: 2.17.3
    ChimeraX-Shape: 1.1
    ChimeraX-Shell: 1.0.1
    ChimeraX-Shortcuts: 1.2.1
    ChimeraX-ShowSequences: 1.0.3
    ChimeraX-SideView: 1.0.1
    ChimeraX-SimilarStructures: 1.0.1
    ChimeraX-Smiles: 2.1.2
    ChimeraX-SmoothLines: 1.0
    ChimeraX-SpaceNavigator: 1.0
    ChimeraX-StdCommands: 1.19.1
    ChimeraX-STL: 1.0.1
    ChimeraX-Storm: 1.0
    ChimeraX-StructMeasure: 1.2.1
    ChimeraX-Struts: 1.0.1
    ChimeraX-Surface: 1.0.1
    ChimeraX-SwapAA: 2.0.1
    ChimeraX-SwapRes: 2.5.2
    ChimeraX-TapeMeasure: 1.0
    ChimeraX-TaskManager: 1.0
    ChimeraX-Test: 1.0
    ChimeraX-Toolbar: 1.2.3
    ChimeraX-ToolshedUtils: 1.2.4
    ChimeraX-Topography: 1.0
    ChimeraX-ToQuest: 1.0
    ChimeraX-Tug: 1.0.1
    ChimeraX-UI: 1.49.1
    ChimeraX-Umap: 1.0
    ChimeraX-uniprot: 2.3.2
    ChimeraX-UnitCell: 1.0.1
    ChimeraX-ViewDock: 1.5.2
    ChimeraX-VIPERdb: 1.0
    ChimeraX-Vive: 1.1
    ChimeraX-VolumeMenu: 1.0.1
    ChimeraX-vrml: 1.0
    ChimeraX-VTK: 1.0
    ChimeraX-WavefrontOBJ: 1.0
    ChimeraX-WebCam: 1.0.2
    ChimeraX-WebServices: 1.1.5
    ChimeraX-Zone: 1.0.1
    click: 8.3.1
    colorama: 0.4.6
    comm: 0.2.3
    contourpy: 1.3.3
    coverage: 7.13.1
    cxservices: 1.2.3
    cycler: 0.12.1
    Cython: 3.1.4
    debugpy: 1.8.19
    decorator: 5.2.1
    docutils: 0.21.2
    executing: 2.2.1
    filelock: 3.19.1
    fonttools: 4.61.1
    frozenlist: 1.8.0
    funcparserlib: 2.0.0a0
    geomdl: 5.4.0
    glfw: 2.10.0
    grako: 3.16.5
    h11: 0.16.0
    h5py: 3.15.1
    html2text: 2025.4.15
    httpcore: 1.0.9
    httpx: 0.28.1
    httpx-sse: 0.4.3
    idna: 3.11
    ihm: 2.2
    imagecodecs: 2024.6.1
    imagesize: 1.4.1
    iniconfig: 2.3.0
    ipykernel: 6.30.1
    ipython: 9.5.0
    ipython_pygments_lexers: 1.1.1
    ipywidgets: 8.1.8
    jedi: 0.19.2
    Jinja2: 3.1.6
    jsonschema: 4.26.0
    jsonschema-specifications: 2025.9.1
    jupyter_client: 8.6.3
    jupyter_core: 5.9.1
    jupyterlab_widgets: 3.0.16
    kiwisolver: 1.4.9
    line_profiler: 5.0.0
    lxml: 6.0.2
    lz4: 4.3.2
    Markdown: 3.8.2
    MarkupSafe: 3.0.3
    matplotlib: 3.10.7
    matplotlib-inline: 0.2.1
    mcp: 1.18.0
    msgpack: 1.1.1
    multidict: 6.7.0
    ndindex: 1.10.1
    nest-asyncio: 1.6.0
    netCDF4: 1.6.5
    networkx: 3.3
    nibabel: 5.2.0
    nptyping: 2.5.0
    numexpr: 2.14.1
    numpy: 1.26.4
    OpenMM: 8.2.0
    openvr: 1.26.701
    packaging: 25.0
    pandas: 3.0.2
    ParmEd: 4.2.2
    parso: 0.8.5
    pep517: 0.13.1
    pexpect: 4.9.0
    pickleshare: 0.7.5
    pillow: 11.3.0
    pip: 25.2
    pkginfo: 1.12.1.2
    platformdirs: 4.5.1
    pluggy: 1.6.0
    prompt_toolkit: 3.0.52
    propcache: 0.4.1
    psutil: 7.0.0
    ptyprocess: 0.7.0
    pure_eval: 0.2.3
    py-cpuinfo: 9.0.0
    pyarrow: 24.0.0
    pybind11: 3.0.1
    pycollada: 0.8
    pydantic: 2.12.5
    pydantic-settings: 2.12.0
    pydantic_core: 2.41.5
    pydicom: 2.4.4
    Pygments: 2.18.0
    pynmrstar: 3.3.6
    pynrrd: 1.0.0
    PyOpenGL: 3.1.10
    PyOpenGL-accelerate: 3.1.10
    pyopenxr: 1.1.4501
    pyparsing: 3.3.2
    pyproject_hooks: 1.2.0
    PyQt6-commercial: 6.9.1
    PyQt6-Qt6: 6.9.2
    PyQt6-WebEngine-commercial: 6.9.0
    PyQt6-WebEngine-Qt6: 6.9.2
    PyQt6_sip: 13.10.2
    pytest: 9.0.2
    pytest-cov: 7.0.0
    python-dateutil: 2.9.0.post0
    python-dotenv: 1.2.1
    python-multipart: 0.0.21
    pyzmq: 27.1.0
    qtconsole: 5.7.0
    QtPy: 2.4.3
    qtshim: 1.2
    RandomWords: 0.4.0
    referencing: 0.37.0
    requests: 2.32.5
    roman-numerals: 4.1.0
    roman-numerals-py: 4.1.0
    rpds-py: 0.30.0
    scipy: 1.14.0
    setuptools: 80.9.0
    sfftk-rw: 0.8.1
    six: 1.17.0
    snowballstemmer: 3.0.1
    sortedcontainers: 2.4.0
    soupsieve: 2.8.3
    Sphinx: 8.2.3
    sphinx-autodoc-typehints: 3.2.0
    sphinxcontrib-applehelp: 2.0.0
    sphinxcontrib-blockdiag: 3.0.0
    sphinxcontrib-devhelp: 2.0.0
    sphinxcontrib-htmlhelp: 2.1.0
    sphinxcontrib-jsmath: 1.0.1
    sphinxcontrib-qthelp: 2.0.0
    sphinxcontrib-serializinghtml: 2.0.0
    sse-starlette: 3.2.0
    stack-data: 0.6.3
    starfile: 0.5.13
    starlette: 0.52.1
    superqt: 0.7.6
    tables: 3.10.2
    tcia_utils: 1.5.1
    tifffile: 2025.3.13
    tinyarray: 1.2.5
    tornado: 6.5.4
    traitlets: 5.14.3
    typing-inspection: 0.4.2
    typing_extensions: 4.15.0
    urllib3: 2.6.3
    uvicorn: 0.40.0
    wcwidth: 0.3.2
    webcolors: 24.11.1
    wheel: 0.45.1
    wheel-filename: 1.4.2
    widgetsnbextension: 4.0.15
    yarl: 1.22.0

[Eric Pettersen]

Hi Xiang,

Thanks for reporting this problem. Though ChimeraX sessions are forwards compatible (old sessions will restore in newer versions of ChimeraX, they are not necessarily backwards compatible (new sessions may not restore in older ChimeraX versions). To restore your session you need to use the ChimeraX 1.12 release candidate or the ChimeraX daily build.

--Eric

Eric Pettersen
UCSF Computer Graphics Lab