You can use the master tome to define what happens when you cast the spell by sneaking. If you sneak while casting a Portal spell, it hides the portal. You can use the tome to set it to close the portal. Otherwise - the portals will stay open until you manually close them.
It is documented on the regular mod page: https://www.nexusmods.com/skyrimspecialedition/mods/104212
7 comments
Are they activated "for ever"?
It is documented on the regular mod page:
https://www.nexusmods.com/skyrimspecialedition/mods/104212
Skin textures are from BNP.