By default, the extension is not available on incognito mode. You need to activate it by opening the extensions manager page (chrome://extensions) and check the "Allow in incognito" option. After the option is checked, the extension will appear in all windows, and JS blocking is covered on both modes.
After installation, the extension is not active by default (JS execution is permitted). Whenever you need to block, click on the action button.
You can define a domain list for both modes. The domains listed on the options page will allow JS execution, even when it is globally forbidden or vice versa. This is useful for those websites like Gmail that do not work without JS being enabled.
The extension auto-refreshes the current tab after the toolbar button is toggled. If this is not your preferred behavior, use the options page to disable this. This is a forced refresh to bypass browser caches (similar to pressing Shift + F5 keyboard combination).
4. Inline events
6. setTimeout evaluation
7. "document.write" execution