Fatal internal error

**Context:** Activation

```python-traceback
None```

**Software versions:**
* Getting Things GNOME! v0.6-20-g55a1a624-dirty
* CPython 3.8.10 (default, Aug 18 2025, 19:30:06)   [GCC 9.4.0]
* GTK 3.24.38, GLib 2.64.6
* PyGLib 3.36.2, PyGObject 3.36.2
* Linux-6.17.0-14-generic-x86_64-with-glibc2.29