Note: This version of 4chan X does not work with Opera 12. If you need Opera 12 support, try loadletter's fork instead.
Install the Userscripts extension. Enable it by pressing ⌘,, navigating to the extensions pane and checking Userscripts chechbox. Now open the Userscripts editor by clicking on the </> button in the taskbar. Then click on the + button and select the New Javascript option. Replace the default text with the contents of the 4chan X script. Finally save it by pressing ⌘s.
Install the Userscripts extension. Enable it by pressing ⌘,, navigating to the extensions pane and checking Userscripts checkbox. Now open the Userscripts editor by clicking on the </> button in the taskbar. Then click on the + button and select the New Javascript option. Replace the default text with the contents of the 4chan X script. Finally save it by pressing ⌘s.
Several minimal browsers have support for userscripts and can run 4chan X. Due to the lack of the cross-site GM_* API, and lack of support for userscripts in iframes, not all features will work. You may experience crashes when repeatedly solving the default image-based captchas. You can avoid this problem by enabling Use Recaptcha v1 in your settings.