First of all we already have topic thumbnails you can enable it from the ACP.
If that isn't enough you can take a look at the code that makes it work and duplicate that.
There's no menu.tpl in the partials directory of the Lavendar theme. Where would you make the changes?
@Chris Vanilla. Or create one.
Nah, I just want to add an icon to the menu. Don't really need to create a theme to do that..
There's a plugin that does this. Or at least shows you how via hooks. on the iPad unfortunately, so can't guide you more specifically, look at the shoutbox plugin code. Should be in there.
What I don't like about the hook though is it just appends the new items to the end of the existing ones...I don't think you can change the order, or remove existing ones. I could be wrong though.
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The menu.tpl for lavender is actually being pulled in from the vanilla theme:
So, just copy the
menu.tpl from vanilla to your lavender partials folder and change as needed.