Hi,
Sorry that you are seeing this issue.
1. Please go to Window > Preferences > CodeMix > Editors > Code Mining
and check if any of the options are enabled. If enabled, disable them, restart the IDE and check if the performance improves.
2. If you are still seeing the issue, then can you please reach us via Live Chat (Help > CodeMix > Live Chat) to help us get some diagnostic information?
Apologies for inconvenience caused.
–Swapna
Genuitec Support