Primary collections web page is out dated - loading is too slow, too static

[min2ha]

Currently there are too many collections for a static load in a single web page.
Fragmented, Dynamic, Lazy loading solution is needed.

[anjackson]

Looks like we're using full-size images as thumbnails, which will a sigificant part of the slowdown I think.

[jasonwebber-bl]

It should be possible to batch resize the collection images? The maximum size we ever need is 500px wide when we use them in blogs etc.

[GilHoggarth]

Would be good if https://www.webarchive.org.uk/en/ukwa/img/47007971.JPG finally corrected.