Corrupt display ?

Hi -

I am using PhpStorm 2023.2.1 and have recently noticed some strange behaviour. I have a html file and if I make ANY alterations to this file, after uploading - the layout seems “off”.  Elements are not aligned as they should. When I say make any alterations, I just need to make any edits to the original file and after uploading - the file does not render as it should. I have uploaded 2 images to show what I mean,

This is the page before any edits.

Then make ANY change (and I mean any change - even pressing a spacebar and saving) and after uploading the page, looks like this :

I have set phpStorm to automatically upload any changes to my remote server via FTP. Has anyone come across this issue ? Or can anyone shed some light as to what may be happening ?

Many thanks.

Paul.