Same here: It almost feels like if IMDB became useless to me since the 'My Movies' enhancer script doesn't work anymore.

I hope you (@AltoRetrato) or someone else will build a new (future proof) script / browser extension.

Like many others have said, I'm definitely willing to contribute to the project.

If not I hope someone will be able to work on a temporary solution mentioned by msschmitt, where we need to download and (re)upload our lists to be able to match it with the script. Anything better that not having the script at all.