Make the copy before changing browsers
Open My List where your saved titles currently appear. Select Create backup and copy the complete text from the box. Keep it in a note or file you control. Do this before clearing browser data or giving up access to an old device.
Merge the copy into the destination
Open My List in the other browser, paste the text into Restore backup and choose Merge backup. Recognized missing titles are added. Existing checkpoints are retained rather than silently replaced, and duplicates are not added to the saved list. Read the result message to see what was accepted.
If the backup is rejected
Check that its first and last characters were included. The backup must belong to VidStream and use the expected format. A list from another brand is not interchangeable. If a title is no longer recognized, the result can skip it rather than creating a broken entry.
Know what the text reveals
It contains title identifiers and completed-episode choices. It is not a movie file and contains no streaming-service login. It can still reveal the films and series you are interested in, so do not post it publicly unless that is intentional.