Rated 5 out of 5 stars

The extension is not dead!
It works with SeaMonkey 2.0.3. Just do the following:
1. download and open your Tab Clicking Options 0.6.9 (addon-260-latest.xpi) with any archiver.
2. find install.rdf.
3. extract install.rdf.
4. open install.rdf with any text editor.
5. find em:maxVersion in the Section.
6. replace 2.0 (or something like that) with 2.1.
7. save install.rdf.
8. replace install.rdf in the archive with your new file.
9. install the extension.
All done, have fun!