Problems with IE10 and SharePoint webpart - Large font sizes

Hello all,

I encountered a problem when backing up the content database from SharePoint 2010 to SharePoint 2013 (and while using IE10). After restoring and adding the content database to SharePoint 2013, I upgraded to UI 2013. My Web Part was assigned a large font size (this was working fine with IE9) because IE10 automatically added an h1 tag outside of the div tag.

I can use the SharePoint Designer to remove the h1 tag. But how can I remove the h1 tag via code behind (or do you have other suggestions)?

Thanks in advance,

/khoilh