Summary: When pursuing a hostile party, my own party's speed drops for no reason. In the linked picture, you can see when I directly target a hostile party on top and when I click on random ground on the bottom.
How to Reproduce: In the uploaded save, move slightly away from the hostile party to...
Works fine when I first load the save, but if I go into the inventory and exit it using the cancel button or ESC, it removes the Footmen on Horses buff from my party speed.
Exiting the menu using the done button works fine.