URL/Link is stuck in cache and isn't updated as the user navigates the site (when using as Block)

In my setup I'm using the ShareThis as a block as it needs to be added into the footer so I don't think the "Page" or "Links area" would work for my requirements. I think this issue is directly related to the block/caching for D8 but I'm not able to test this at this time.

It seems to get cached with the first URL the user hits. As an logged in user it's their /user/{uid} page but for anon users it's whatever frontend page they accessed.

I'm on (node/4), If I clear the cache and access another page (node/95) to test the st_url correctly reflects the new page (node/95) but if I navigate away (to node/26) it still shows the new page link (node/95).

It doesn't seem that there are settings under Conf -> Performance to control the block caching in D8, or settings in the ShareThis module page to control anything. I've also had a look through the settings.php and settings.local.php files to see if there is anything there but there doesn't appear to be anything to control block specific caching.