> Does make me wonder why there isn't an ALGPL: "Use my network-expressed component as you like, but if you alter its source, you also need to redistribute the changes under the same license"…
I'm fairly sure there's a GPL like that, either the GPLv3 or a version of the AGPL. It definitely doesn't let you alter the source for network servers, though, exactly like you say.
"It has one added requirement: if you run a modified program on a server and let other users communicate with it there, your server must also allow them to download the source code corresponding to the modified version running there."
Notably, the Canvas learning management system is licensed this way, and all of their JavaScript is unminified so you can download it from the server.
I'm fairly sure there's a GPL like that, either the GPLv3 or a version of the AGPL. It definitely doesn't let you alter the source for network servers, though, exactly like you say.