'ProblemTable' object has no attribute '_columns'

[AlexanderGo99]

Application Name: dupeGuru
Version: 4.3.1
Python: 3.9.2
Operating System: macOS-15.7.3-arm64-arm-64bit

Traceback (most recent call last):
File "qt/table.py", line 105, in headerData
AttributeError: 'ProblemTable' object has no attribute '_columns'