I'm not sure how to do that. Neither of the two symbols shown in your screen shot show on my screen.
Top right of screen is your user name, click on that
User Control Panel
Find "Your Control Panel", follow that down to "Edit Options", click on that
In Edit Options there is a Forum Skin option
I use "New Mobile Friendly 2+2", but there are quite a few options
Hi. I see a lot of spam but no way to report it from Mobile on the new software so here you go. The image uploader also seems to be half broken though so I give up
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