[1.20.4] NeoForge version doesn't load at all

Minecraft version: 1.20.4
NeoForge version: 20.4.237
NERB version: 0.4

When loading by itself with no other mods installed (and with other mods, but that shouldn't matter here), the game crashes with exit code 1.  No significant logs, no crash report, and no Java crash...  The game simply refuses to load.