Traceback (most recent call last):
File "/home/balazs/.local/share/QGIS/QGIS3/profiles/default/python/plugins/CityJSON-loader/gui/cityjson_loader.py", line 91, in select_cityjson_file
self.clear_file_information()
File "/home/balazs/.local/share/QGIS/QGIS3/profiles/default/python/plugins/CityJSON-loader/gui/cityjson_loader.py", line 123, in clear_file_information
self.dlg.metadataPlainTextEdit.setPlainText("")
AttributeError: 'CityJsonLoaderDialog' object has no attribute 'metadataPlainTextEdit'
Just came across this today with version 0.4.0:
Python version: 3.6.8 (default, Jan 14 2019, 11:02:34) [GCC 8.0.1 20180414 (experimental) [trunk revision 259383]] QGIS version: 3.8.2-Zanzibar Zanzibar, e0a5e94093
Let me know if you need the data that I tried to load.