macOS Tahoe app fails to start with "NameError: name 'QtCore' is not defined"

[colini]

Describe the bug
I've just installed VocabSieve-v0.12.5-macos-x86_64.dmg on macOS Tahoe 26.2 (arm macbook). After removing the quarantine flag I tried to launch the application. From the GUI it shuts down immediately. When I tried to run from the terminal it fails with:

$ /Applications/VocabSieve.app/Contents/MacOS/app 
Traceback (most recent call last):
  File "/Library/Frameworks/Python.framework/Versions/3.11/lib/python3.11/site-packages/cx_Freeze/initscripts/__startup__.py", line 121, in run
  File "/Library/Frameworks/Python.framework/Versions/3.11/lib/python3.11/site-packages/cx_Freeze/initscripts/console.py", line 25, in run
  File "app.py", line 1, in <module>
  File "/Library/Frameworks/Python.framework/Versions/3.11/lib/python3.11/site-packages/PyQt5/__init__.py", line 59, in <module>
NameError: name 'QtCore' is not defined

To Reproduce

• Install from VocabSieve-v0.12.5-macos-x86_64.dmg
• Remove quarantine flag with xattr -d com.apple.quarantine /Applications/VocabSieve.app
• Launch via the Finder or terminal

Expected behavior
I expected the gui to launch.

Screenshots
If applicable, add screenshots to help explain your problem.

Logs
Go to Help->View session logs, paste the log here. Be sure to redact out any sensitive information. The log can contain clipboard content.

Desktop (please complete the following information):

• OS: macOS Tahoe 26.2
• Vocabsieve version (if nightly, must be latest): v0.12.5-macos-x86_64

Additional context
Add any other context about the problem here.

[dougalg]

I also have this issue on Seuquoia 15.6.1