## Manual installation from a system installed package

1. Menu > Help > More Troubleshooting Information.

2. Application Basics > Profile Directory > Open Directory.

3. Open directory in a terminal.

4. Create a `chrome` directory if it doesn't exist:

	```
	mkdir -p chrome
	cd chrome
	```

5. create a symlink to the actual theme location:

	```
	ln -s /usr/lib/thunderbird-gnome-theme thunderbird-gnome-theme
	```

6. Create single-line user CSS files if non-existent or empty (at least one line is needed for `sed`):

	```
	[[ -s userChrome.css ]] || echo >> userChrome.css
	[[ -s userContent.css ]] || echo >> userContent.css
	```

7. Import this theme at the beginning of the CSS files (all `@import`s must come before any existing `@namespace` declarations):

	```
	sed -i '1s/^/@import "thunderbird-gnome-theme\/userChrome.css";\n/' userChrome.css
	sed -i '1s/^/@import "thunderbird-gnome-theme\/userContent.css";\n/' userContent.css
	```

8. Symlink preferences file:

	```
	cd .. # Go back to the profile directory
	ln -fs chrome/thunderbird-gnome-theme/configuration/user.js user.js
	```

9. Restart Firefox.

10. Open Firefox customization panel and move the new tab button to headerbar.

Done. See README.md for more details.