So, in the Vesteria Limited Public Testing Place, I was hopping off mushrooms then I flew out the map. It took a couple moments to respawn, but when I started running, the stamina bar wasn’t there and I was unable to be exhausted. So basically, it renders DEX useless until you respawn I believe. If you die in means other than resetting or dying from a monster or die in any means which you don’t lose any HP, you gain the ability to ignore stamina and run forever using Shift.
Edit: Here’s a gif after falling off the map of me running without a stamina bar.
Also I’m pretty sure I got this bug before on the actual game because I was able to run infinitely.