Images are generally the heaviest assets on a webpage- so if you’re interested in fast load times for users, this is one of the best places to optimize.
Lazy Load Your Images
One popular technique for speeding up the initial load time is called “lazy loading”. It works by replacing the source of images (src=”/example.gif”) with a transparent placeholder image (src=”/pixel.gif”). This allows everything else on the page (text,fonts,scripts,etc) to render first. Continue reading →
Update: Menu items now have the class “menu-item-has-children” that can be used for styling thank to this core ticket. So, the menu walker is no longer needed.
I think it’s important to give users a visual cue when menu items have a drop down menu.
One way I’ve handled this in the past is to use the Superfish jQuery plugin, which adds a class to any list items with children. This allows them to be styled differently- with a background image of a down arrow (for instance).