You do not need an extension to browse here
Search, posters, film details, episode guides and the local saved list are part of the NetFilm website. They do not require a browser extension. If you came from an old tutorial that says an extension must be installed first, that instruction may describe a different version of the Netfilm.app experience rather than the page you are using now.
Why older instructions still appear
A historical Netfilm Extension listing was associated with the earlier app website. An old listing or screenshot can explain a familiar name, but it does not establish that the package remains supported or that it restores an old player's sources. This site provides no extension download, installation or compatibility promise. The current viewing action opens the selected title's options through JustWatch.
Recover the show instead of the old setup
If your real aim is to continue a series, start with the title, season and episode. Search those details, open the guide and match the episode name. That information is useful across devices and websites, whereas an obsolete package version usually is not. Keep a checkpoint for the last episode you completed and save the series to return later. Use episode help if you cannot reconcile the numbering.
If a page fails before you even reach a title, the not-working guide separates page loading, catalog results and external video problems.