Hi Rottadamic, Thanks for your feedback! If you want to keep the hidden result after you apply another cloth, please use Hide Body Mesh Tool. Currently, the show/hide adjustment of edit mesh will be replace as Cloth's hide mesh settings after you apply the new cloth to character, but if you use Hide Body Mesh first, it will keep it. Calvin Reallusion.
Yes... I found this bug too ... https://www.reallusion.com/FeedBackTracker/Issue/Hiden-Faces-in-Mesh-Editor-reappear-when-applying-cloth-from-the-content-manager And you are right... very annoying ... hopefully fixed soon! :)