@Markster I don't think that is possible (easily).
Can you navigate quicker the second time accessing those scripts?
Can you pause or restart Unbound and see if that fixes it for you?
Yesterday, I updated many routers to Skynet v7.1.1 and the only one that seemed a little slow was an original 'classic' RT-AC68U and an RT-AC66U_B1 model. But no errors and after a few minutes of letting the router idle, things were working fast for those too.
How long since you've rebooted the router? Mine is now almost 9 days without issues.
Depending on the updates that were done, maybe a reboot may help?