Uploading your own images? This might be useful.

Useful image optimisation – great for anyone uploading their own content to social media or website. Just drag and drop your image onto the web page and TinyPNG will compress your .png and .jpg files.

.png files are really popular as they can be transparent and overlaid when building web pages, but they can be large in file size. This tool will help maximise quality while keeping the files small. It also optimises .jpg so there’s no excuse!

https://tinypng.com/