• Download uBlock.safariextz (latest release desirable)
• Open the downloaded extension
• In Safari's popup:
  • Click Trust

For now, when installing manually, updates will not show up in Safari's extensions panel. Therefore, you will have to repeat this process to update. For some users, updating manually is actually an advantage because:

• You can update when you want
• If ever a new version sucks, you can easily just re-install the previous one

If clicking Trust does not work, you may need to use keyboard controls:

1. Launch System Preferences and open the Keyboard pane.
2. Switch to the Shortcuts tab.
3. Toggle All Controls to selected.
4. Re-attempt to install the extension and use the Tab key on the keyboard to highlight Trust.
5. Press the Space bar key to press the Trust button once selected.