The dot is hard coded. Why is it hard coded? Because if the webmaster wants it in a different format then they can just construct a dropdown box manually using their own HTML (instead of the keyword [[tld-dropbox]]).
Thus, you have two options:
Recommended:
You can copy the HTML that is currently generated by [[tld-dropbox]] and remove the dots. Then you can place the modified html in the templates in place of [[tld-dropbox]].
Not Recommended:
Modify classes/display.php : Edit the following on line 330:
PHP Code:
$searchbar .= "<option value=\"{$ext}\"{$selected_text}>.{$ext}</option>\n";
and replace .{$ext} with simply {$ext}
The reason I do not recommend the second option is that it will be overwritten when you update the script while the first option will remain in tact through updates.