My header menu clusters together upon loading

hi I was wondering if some could help, please. I am using the ocean wp theme and I have a problem with my header menu.

When the menu loads or I move from one category to the other on the menu tabs on the odd occasion the menu clusters and squeezes together for a couple of seconds and then goes back to the normal layout.

I’ve checked all my settings but can’t seem to work out what could be causing this. any ideas?

My page is usually on maintenance mode but you get in touch I could switch that off.

Thanks in advance

Kate

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