A Snap application that starts failing after an update may support reverting to a retained earlier revision. This can be a useful comparison, but it is not a complete restore of everything the application has touched. Decide what data must be preserved before changing the installed revision.

Capture the starting point

Save current work and close the app. Record the failure, the installed revision and the operation that triggers it. Use snap list --all to inspect retained revisions and distinguish the active version from entries marked disabled.

Preserve important documents and use any application-specific export or backup needed for its database. Canonical explains that a revert changes the application revision and its associated configuration, while data stored in common locations may not be reverted. An older app can therefore encounter data already changed by the newer version.

Confirm that the publisher supports opening the current data with the earlier revision. Where that compatibility is uncertain, ask for guidance rather than using the only live dataset as an experiment.

Compare a controlled workload

An administrator can use sudo snap revert followed by the exact installed snap name to return to the available prior revision. A particular retained revision can be selected with the documented revision option when there is a clear reason to choose it. Record the resulting version before opening a disposable sample.

Repeat the original failing operation on the sample and note the result. Success on launch alone does not establish that saving, exporting or reopening work is reliable. Keep the original evidence so that the publisher can compare the two revisions.

Reverting does not change the channel the snap tracks. Canonical also distinguishes the revision just reverted from from later new revisions: a future different revision may still arrive automatically, and a targeted manual refresh can reinstall the current release. Agree the next update and retest step instead of assuming the revert permanently freezes the app.

Sources: Snap documentation.