Missing search icon in navigation bar

My search icon isn’t loading, it’s just a square. I’ve emptied the cache, disabled plugins and cannot figure out what’s causing it.

Please can anyone help? It just randomly disappeared one day, I rarely do anything to my site so it didn’t disappear after installing any new plugins or doing anything.

• This topic was modified 3 years, 5 months ago by Jan Dembowski. Reason: Moved to Fixing WordPress, this is not an Everything else WordPress topic

The page I need help with: [log in to see the link]