content 'flash' in Chrome...

[MattAppleton]

Hello — bricklayer working OK in this preview site :: https://gresfordarchitects.co.uk/projects

But Chrome is giving a strange 'flash' of a large content item each time the page is accessed... (try clicking the 'project' button several times... this issue seems specific to Chrome...

Any clues as to what this might be?!

thanks