Create a copy before you need it
Open Watchlist and choose Create backup. Copy the entire text from the output field. Keep it somewhere you can find again, such as a private note or text document. It contains saved production identifiers and series checkpoints, not movie files or a portable copy of the website.
Merge in the destination browser
Open MovieWatcher in the browser where you want the list, return to Watchlist and paste the text into Restore backup. Choose Merge backup and read the status message. Titles already saved are not added again. Existing checkpoints in the destination are retained, so a backup does not overwrite a newer place in a series.
If the import is rejected
Check that you copied the complete text and that it came from MovieWatcher, not another brand's list. Do not remove punctuation or edit title identifiers by hand. An incomplete or unrelated backup is rejected rather than guessed at. Invalid episode checkpoints are not treated as valid progress.
What a backup cannot recover
If browser data has already been cleared and no copy exists, an unrelated login will not restore the list. Private sessions can discard local data when closed. Create another backup after making changes you want to keep. Recently browsed pages are a separate convenience and are not included as a complete viewing history.