@gijo
I can confirm I have this very exact same problem on several websites.
Anything related to cart page is not working such as adding, updating, deleting, the cart page does not reflect until you manually hit F5 on the cart page then it suddenly updates.
I already triple check all settings. I have added exclusion words.
By default your plugin already adds /cart but still it does not work.
I also have some pages in other names in my language and added /winkelmand but still this does not work.
And it is 100% coming from your plugin because when I disable it, everything works back to normal.
Since I can replicate this exact bug over and over on multiple websites, this is no coincidence.
Either there is a bug in the way how your plugin handles interactions with the cart or that wordlist is ignored for cart page.
If you want to troubleshoot more indepth, let me know how I can contact you and happy to help you improve this.
Thanks
Fabio