Upgrading from v2
If you used a version of Lex Cloak from v1.8 or earlier, saved sessions from that version were removed in the upgrade, because the way sessions are stored changed. Your documents were never touched and nothing else is affected. Choosing Got it on the notice clears the old session data and you can keep working as normal.
What changed in the upgrade
Earlier versions of Lex Cloak kept work-in-progress in a hidden folder inside the app. The current version keeps it next to your document as an opt-in sidecar file you can see and manage, called the working session. The way sessions are stored is therefore different from v1.8 and earlier, and the upgrade does not migrate the old saved sessions across.
Your documents are unchanged. Lex Cloak never moves, modifies, or uploads your source PDFs, and the upgrade did not touch them. The change is only to where work-in-progress lives.
What the migration notice does
The first time you launch the upgraded app, Lex Cloak shows a one-time notice if it detects a v1.8-or-earlier session folder on your machine. Choose Got it and the app clears the old session data, then continues into the normal interface. The notice does not appear again, and your documents are not affected by the cleanup.
If you were partway through redacting a document in v1.8 or earlier, the redacted file you already saved is on disk and still valid. The working state was the part that did not carry over. Open the source PDF in the upgraded app and review it from scratch, using the new working session model so the work-in-progress can be saved as a sidecar this time. See working sessions.
After the upgrade: keeping current
On Windows, Lex Cloak now uses an auto-updater. When a newer version is available, a banner appears below the version number in the sidebar. You can install the update from there, and Settings has an auto-install option plus a Check for Updates button if you want to look manually. On macOS, the app checks for updates and notifies you when one is ready to download.