This custom CSS tester allows you to load a custom CSS to Twitcasting Live Chat Comment ovrlay so that the customized comment ovelay can be viewed on your Web browser.
The loaded CSS can be debugged with browser's built-in developer tools.
Please start in the extension's option page to set-up and open a comment overlay URL. Once a comment page is opened, the popup page can be used to temporarily edit and hot-reload the custom CSS inserted by this extension.
Support Page: https://kii-memo.blogspot.com/p/custom-css-tester-twitcasting.html (In Japanese)