As usually, copy this directory under the ~/.tkabber/plugins directory
so that you get a hierarchy like this:
  ~/.tkabber/plugins
  ~/.tkabber/plugins/hidemuctopic/
  ~/.tkabber/plugins/hidemuctopic/hidemuctopic.tcl

Restart Tkabber, to get the plugin loaded.

Navigate "Tkabber->Customize->MUC Hide Topic" group of settings
where you can specify where or not to hide the topic window
automatically in MUC rooms when they're opened.

You can toggle visibility of the MUC topic window by pressing
<Ctrl-t> while the chat input window has keyboard focus.

Consult the README file for the details about using this plugin.

