OS: macOS 12.6 (21G115)
wtfutil version: a633292 (2022-10-05T15:08:35Z)

I installed wtfutil via homebrew. I started it with custom config (e.g. wtfutil --config=/Users/ivanmilosavljevic/.config/wtf/ivan_config.yml). This custom config was just a copy of provided default config. Then I started making changes, like changing positions, width and height of modules, or adding a new module, removing a module etc. After every save of config file the CPU usage of wtfutil went up by 100% (so after 7 saves => 700%).