Hello @annaadam,
Hubspot should minifie your own CSS and JS, but for downloaded scripts you need to embed the minified version
i can refere to: Site Speed and Performance: What you can do, and How HubSpot Helps
You are using different JavaScript files, which are loaded in like for example slick.js, try to change it to the minified version like: slick.min.js
Normally if you download the scrips there is a miniefied version in the folder.
You have a couple of script which can be changed to the minified version; here is short list, which i found:
jquery-ui.css
bootstrap.css
animation.css
slick.css
bootstrap.min.js
easing.js
wow.js
slick.js
jquery.mixitup.js
jquery-ui.js
For the security error, this is because Hubspot uses an old version of jQuery 1.7.X or 1.11.X, if you want to fix this issue you need do exclude the Hubspot jQuery and embed your own version.
You can exlude jQuery in: Settings - Website - Pages
I hope this helps you
- Chris