Well, there nothing random in our meta tag mod.
Forum description is used for the meta description, so you can already edit them in acp as you wish, and for topics, I'm not sure that such customization would be worth it. It would be ok for few, but would be very hard to deal with big boards.
Then, have you read this post about phpBB3 meta tag optimization :
http://www.phpbb-seo.com/boards/phpbb3- ... t3472.html
?
If you restore word filtering in the indexing, you'll be able to use higher common words threshold and have the better keyword showing up. You can also choose to bypass the search table query and only use words from the first post.
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