Addon/script/etc to install all addons from AMO?

[James]

Also some current versions of Extensions hosted at a.m.o are supporting only recent versions of Firefox as you may need to go into the Extensions versions history to install a older version that was compatible with Firefox 24. The Extension version made for say Firefox 29.0 and newer may have been updated for the new UI in mind and may not work with Firefox 28.0 and earlier for example.

[Trippynet]

Yeah, the one I tested for that was Classic Theme Restorer, simply because I knew off the top of my head that it was only for FF29 and later. Obviously I didn't actually install it, it was just to try things out. Didn't try any other extensions though. That info about different behaviours depending on how closely matched the versions are is very interesting though!

[Drumbrake]

This is weird,I've also tried with CTR and the original poster is right,you can only save as .xpi file the current version,the other versions in history cannot be saved.

I've quickly tried with another user agent and/or disabling javascript,that does't work either-and the thing is,if I'm not mistaken this used to work a while ago.

You can get the real address of the extension you want to download using Inspect Element in the right-click menu,however.

Turning JavaScript off will allow you to bypass the page's checking system. Firefox or SeaMonkey may still not allow the extension to be installed, though.

That's exactly what I too seem to remember,but apparently things have changed:I can't even download an incompatible extension,save the current version,all other links to previous versions now are just redirecting there.

[avada]

In SeaMonkey, if the extension/theme claims to work with your version, the button is green. If the extension/theme works up to SeaMonkey 2.1, the button is gray but clickable like Trippynet's image above. If the extension/theme is compatible with anything less than SM 2.1, the button is gray and not clickable.

Turning off JavaScript will turn the button blue in all cases and clicking it will try to install in SeaMonkey. Right clicking it will allow you to download the extension/theme. I'm sure it would do the same in Firefox.

So, the button does different things depending on how far back the add-on claims for compatibility. Turning JavaScript off will allow you to bypass the page's checking system. Firefox or SeaMonkey may still not allow the extension to be installed, though.

This makes sense. Thought that it works different for a reason or another.

The blue button thing doesn't work though in the versions section. It just links back to the main area. So you can only install the latest version or a the latest dev (if present).

[avada]

Yeah, the one I tested for that was Classic Theme Restorer, simply because I knew off the top of my head that it was only for FF29 and later. Obviously I didn't actually install it, it was just to try things out. Didn't try any other extensions though. That info about different behaviours depending on how closely matched the versions are is very interesting though!

With CTR specifically you can install 1.2.1, but you can't install/download 1.2.1beta11.
They both have the same min version so it's not as straightforward as smsmith suggested.

With Greasemonkey nothing after 1.15 can be installed/downloaded.