I have no idea when this feature was added, but I’ve wanted to clear out useless Demo boards for a long time. This is extremely cool! Thank you so much =D
For those wondering how, go to Game Information (same side screen you’ll find Download SGF and Analyze Game in). At the bottom right corner of this screen is a Delete button 
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I see that it is also possible to delete reviews.
This thread deserves a bump – I wasn’t aware of the feature.
Awesome, just deleted all my trashes.
I wasn’t aware either, even though I looked for it.
Great, but maybe there’s a slight UI problem here if nobody can find it !
Equally well hidden is the site manual: Documentation and DAQ (see bottom of screen shot). Click on three lying bars (top screen shot) to get to this menu.
The thing is you delete the review but it’s not fully deleted.
It doesn’t appear any more at the top of the game you reviewed and in your review list. But it’s still there in the chat of the game and you can access it.
So this is a problem in some way if you want to fully delete a review, like if you don’t agree anymore on your comments for example.
I also vote for this getting sorted out. I feel the more friendly the tools become for folks who use the site heavily for studying, the better. I know it isn’t a top priority with so many potential new features and other fixes to be considered, but it is worth mentioning. Good catch Groin 
