As mentioned many times before (I should add this to the FAQ part), it depends on the website, this observation is not global. Many servers provide filename extensions one way or another, but e.g. twitter doesn't in any way (because websites don't need to) and my addon can't just take a wild guess as it. There will be an extension if the extension is communicated by the server as per standards. What a blown-out-of-proportion thing to give a permanent 1 star for anyway, as if that's all there is to it and as if it's any addon's fault a server decides not to expose extensions. Stupid "reviews" - more like baseless whines - like this are why I'm done developing for the public anyway.

Some websites do things to stop addons like this from working, and I can't change that. But the addon definitely works on sites that don't take such countermeasures. I use it myself in the latest firefox, as do many other happy reviewers. Don't use reviews for misplaced and false bug reports, they belong in an email with proper information like which site you're trying to use it on. Simply writing "doesn't work" is an utter waste of everyone's time and blatantly wrong.

Sorry but I'm using firefox and this addon myself, and it definitely works, as it does for other people too. There are some sites that do things that prevent addons like this from working (e.g. clickable overlays on images), you may be trying to use it on such a site. Fair enough it doesn't work then but that's no basis to say this addon never works. Please use reviews only for serious, well prepared review content.

Glad you like it, I too used it more often than the titular feature actually

Thank you for knowing what you're talking about before commenting and having realistic expectations unlike some people.

Filenames and extensions depend entirely on the hosting server. Renaming using a.o. the page title is implemented but not supported by firefox itself. Thank you for the reasonable rating, all things considered, unlike the way some people rate projects.