Snap Revert Limits in KDE Neon: Unresolved Behavior After Failed Upgrade

Goal

When a Snap package upgrade fails on KDE Neon, the snap revert <package> command is the documented mechanism to return to a prior revision. However, the scope of what is actually undone—especially configuration files, system‑wide changes, and revision retention—has not been fully clarified.

Constraints and Uncertainty

• The rollback preserves user data stored in the Snap’s data directories, but it is unclear whether configuration changes made by the new revision are automatically undone.
• Only revisions managed by Snap are available for revert; it is unknown how many revisions are retained per package on KDE Neon.
• System‑wide updates performed by apt or other package managers during the same upgrade cycle are not affected by snap revert, raising questions about comprehensive recovery.

Open Questions

1. Does snap revert automatically restore configuration files that were altered by the newer revision, or must these be cleaned up manually?
2. What is the maximum number of Snap revisions retained by KDE Neon for a given package, and how can a user verify or extend this limit?
3. In a scenario where a Snap upgrade coincides with an apt kernel update, can snap revert be used to roll back the kernel, or is a separate mechanism required?