First release of Portals for RP Engine

• Rings of sparks with a live window onto the far side: its blocks, plants, water, biome colours, light, sky and clouds, from wherever you stand.
• Walk through and come out of the other ring still moving the way you were, in the same world or another.
• /portals mark sets where your portals lead and /portals place opens a pair in front of you.
• Right-click a portal to shut it down to a small glowing ball and open it again; sneak and right-click to take it away.
• A permission for every command and for acting on other people's portals.
• An API and four cancellable events for other plugins.
• Needs RP Engine 0.2.10 or newer, on Paper 26.2.