I made a little sequence that can resume playback of where you stopped.
Say you only see half of a movie, then this sequence will save the position you stopped at and resume at that position - 2 minutes when you cast the same movie again.
The important thing is to stop the playback on the Chromecast, if you only take back the movie to your computer/phone/tablet then it will not be saved.
It also does not save the position if you seen less than 10 minutes, or if you have seen more than [media_duration] - 3 minutes.
The only thing you actually need to change in this sequence is the name of the chromecast in the events state node (top left), and the call service node (top right).
You could possibly add more sensors and have it remember more, but I find 9 more than enough.
If you want to do so then edit the large switch node and add another entity node with the same name convention.
You need to install this custom integration for it to work.
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