Blank Images on pages and posts

Thanks for the great plug-in, it has speeded up my site tremendously!

One problem, any images in posts or on pages have just become a blank box. Links from the boxes work fine. Images inserted into side bars via widgets work too. Is there a way of creating an exception for the images I want to appear? My website is https://www.footymystic.com and the problem can be seen clearly on this page https://www.footymystic.com/free-bets/

If there is no fix for this, can you confirm it’s something that might be fixed in the future?

Thanks

Jason

https://www.ads-software.com/plugins/speed-booster-pack/