For Glass.Mapper BeginRenderLink described as method to render a link that should contain multiple HTML elements: http://glass.lu/docs/tutorial/sitecore/tutoria
As it seems this is a known issue with Glass and there is already a pull request pending for it (https://github.com/mikeedwards83/Glass.Mapper/pull/73).
I guess the only way to fix it is to get the latest version from GitHub make the fix and recompile the Glass with your fix. Otherwise you can wait for the pull request to get approved and update your Glass version. As you can see the fix is not that hard (taken from here):
if (IsInEditingMode && isEditable)
{
if (attrs != null)
{
attrs.Add("haschildren", "true");
return MakeEditable(field, null, model, attrs, _context, SitecoreContext.Database, writer);
}
return MakeEditable(field, null, model, "haschildren=true", _context, SitecoreContext.Database, writer);
}