[nybble41]

> … just because something is open source does not necessarily mean that it will stay alive in the way you describe it - especially redesign or new features.

True, being open source doesn't guarantee that the app will be maintained. It does, however, provide the legal framework to make it possible. If the app has an active user base then it's likely that someone would step up to take over the development, and the open source nature of the project means that the new maintainers are not starting at a significant disadvantage.

> My point was mainly in the context of Electron desktop apps, an abandoned, proprietary Electron app would probably run for at least 5 years * without touching it after it's abandoned. Further from that point patching it so it works would not be that hard.

Okay, so you're assuming an app distributed mostly in source form to begin with. That's fair, but an Electron app can be minified or obfuscated (and in the case of a proprietary app, probably would be) so it wouldn't necessarily be easier to work with than a compiled binary. You also still have the copyright issues which would make it difficult to collaborate on any patches.