I had a fail-to-launch for a different but maybe related reason: I had UV_PYTHON_PREFERENCE set systemwide to encourage uv to use the Python installs I already have. But that conflicted with Anki’s lancher:
Anki Launcher Checking for updates... Unable to check for Anki versions. Please check your internet connection. Error: Failed to run (2): /Applications/Anki.app/Contents/MacOS/uv run --no-project --no-config --managed-python --with pip-system-certs --python 3.13.5 /Applications/Anki.app/Contents/Resources/versions.py: error: the argument '--managed-python' cannot be used with '--python-preference <PYTHON_PREFERENCE>'
It persisted when I updated to the prerelease. But Anki launched successfully once I removed that environment variable.
On a quick glance, I would have thought anki/qt/launcher/src/main.rs at 2fee6f959b66f35a2d7d68558895a2f95d439e18 · ankitects/anki · GitHub would have avoided this issue. But maybe the update check flow might be happening before that code runs?