I don’t know if this happened when I updated to Mojave, or the update for Amphetamine…but my MBP only stays awake for a minute or so before the screen saver kicks in.
I have Amphetamine set to “Indefinitely” and I have the Energy Saver on the MBP set to never sleep or put the display to sleep, and the screen saver set to never engage.
Hard to get much work done when I’m putting my password after every idle minute.
Ideas?
That’s odd behavior since you have the Energy Saver to never sleep. Do you have a Hot Corner that could be starting the screen saver?
Maybe amphetamine needs permissions in System Preferences to work its magic?
I think the 15 characters is an attempt to cut down on spam posts since It forces people to think about how descriptive the title really is to the topic at hand.
Also, Help!!! titled posts 
Ah! You helped me crack the code John!
Seems that the default preference in Amphetamine was to engage the screen saver…after 1 minute.
Your suggestion to look at System Preferences for Amphetamine did the trick.
Thanks!