Third-party embeds can quietly add significant loading overhead to Squarespace pages through extra scripts, network requests, and processing. To improve Squarespace loading speed, reduce unnecessary embeds, limit sitewide scripts, and use lazy loading or lightweight alternatives for videos, feeds, and widgets.

Read Blog: https://ok-gud.com/blogs/192191/How-Third-Party-Embeds-Affect-Squarespace-Loading-Speed