I was one of the first to receive a Prusa XL Multitool printer. From the start, I had problems tightening the belt equally on both sides and still aligned parallel so that there is no gap on either side.
Since I've spent a lot of time researching the problem, I know many people have this problem. So I tried a lot of things and have finally found a working solution!
https://investegate.de/prusa-xl-belt-tension-alignment-calibration-guide
The author marked this model as their own original creation.