This plugin works like what the multiplayer plugin does to keep the game running in the background. It'll update the game about once or twice every seconds.
When the game is suspended, time only moves forward by one deltatime unit every tick (so, a tick, but it's worth noting). Every X seconds seem to not work as intended (or at least, they're extremely slow because of that time thing.
Just keep that in mind. wallclocktime will keep working as intended though!
So "Every X seconds" would instead be "Compare two values: wallclocktime - lastTime >= X seconds" when suspended.
Also, system has a "Is Suspended" condition that usually is always false (except in very specific situations where plugins wake up the runtime, aka multiplayer) and that will be true when suspended and the plugin is enabled.
You can disable the plugin while it's suspended, and it will stop waking up the runtime. Meaning no code will run until the game is resumed.