Note that by default the extension is not available on incognito mode. You need to activate it by opening the add-on manager page and checking "Allow in incognito". After the option is checked, the extension will appear in all windows and blockage will occur in both modes.
Note that after installation the extension is not active by default. Whenever you need blockage, simply click on the toolbar button.
For more info about how to use this extension please visit:
For bug reports please visit:
As of version 0.1.5, you can define domain list for white-listing. This means domains listed in the options page will allow JS execution even when it is globally forbidden. This is useful for those websites like Gmail that do not work without JS being enabled.