Super slow performance when there are lots of "a" html tags

I am displaying an HTML, having about 200 **a** tags, the initial load and display of html is super slow.

When I modify **IsBlockAssignableToBox** function, so it does not add **a** tags, the performance issue is resolved ( and offcourse a tags are not rendered as links)

modifed **IsBlockAssignableToBox** version :

```
private static bool IsBlockAssignableToBox(CssBox box, CssBlock block)
{
bool assignable = true;
if (block.Selectors != null)
{
assignable = IsBlockAssignableToBoxWithSelector(box, block);
}
else if (box.HtmlTag.Name.Equals("a", StringComparison.OrdinalIgnoreCase) && block.Class.Equals("a", StringComparison.OrdinalIgnoreCase)
// && !box.HtmlTag.HasAttribute("href")
)
{
assignable = false;
}

if (assignable && block.Hover)
{
box.HtmlContainer.AddHoverBox(box, block);
assignable = false;
}

return assignable;
}
```

Start by profiling the IsBlockAssignableToBox function while loading an HTML document with about 200 a tags, then compare the normal path with the reported modification. Done means the document renders links without the severe initial-load slowdown; the issue does not name a test or source file beyond this function.

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