Quick answer: Unity Input Action Asset edits reverting after restart? Click Save Asset in the editor — the input editor doesn’t auto-save like the rest of Unity.
A designer rebinds Jump to Space, plays for a while, then closes Unity. Next session the binding is back to default. The asset never wrote to disk.
Save Asset Button
The Input Action editor has its own Save Asset button at the top. Edits stay in memory until you click it — closing the editor or hitting play does not auto-save.
Enable Auto-Save
There’s a checkbox: Auto-Save. Tick it. Every change persists on focus loss. Pay a tiny cost for not losing work.
Source vs Generated
If you use Generate C# Class, regenerate after edits. The C# wrapper is generated from the asset and goes stale otherwise.
Verifying
Edit a binding, close Unity, reopen. The binding persists. PlayerInput component finds the action without a missing-reference warning.
“Input Action edits don’t auto-save. Hit Save Asset or enable Auto-Save.”
Auto-Save defaults to off, which trips up every new team member — turn it on in your project’s onboarding doc.