Create the copy while the list is available
Open Bookmarks and choose Create backup. Copy the complete text, including the opening and closing braces, into a place you control. The backup contains recognized title references and saved episode checkpoints. It is not a movie download and does not include an account password.
Merge into another browser
Open the same Bookmarks page in the destination browser, paste the complete backup into Restore backup and choose Merge backup. Recognized saved titles are added. Existing destination checkpoints are kept rather than replaced, which helps protect progress you recorded there after the backup was made.
Read the result
Open the list after merging and check the films or series you expected. If a message says the text cannot be read, compare it with the original complete copy. Do not repeatedly remove random characters to force an import. A backup from another brand or an unrelated desktop application is not the same format.
Keep the distinction clear
Removing a title from Bookmarks is not the same as deleting a browser's site storage. The latter can also affect local preferences and checkpoints. Before any broader cleanup, keep a copy of the information you want. If you lose a list without a backup, this site has no account-based cloud copy to reconstruct it automatically.