All 4 browser extensions have been updated to support manual generation of new addresses. Here's how it works:
When you click the Throttle icon in your browser's navigation bar, the popover will now contain a button to manually generate an address for the current domain you're on (this is because Throttle needs a domain to associate with your generated address — so browse to the right one first).
This feature will come in handy in a number of edge cases. One is if you need to generate multiple addresses for the same page (the normal way will always return the same address for a domain, to make using logins dead simple, but some websites have multiple different signups on one page). Another is if you need to sign up for something that doesn't have an email form.
If you don't see the feature yet, you may need to force your extension to update through preferences (not all browsers auto-update immediately).
Also, if you had noticed the bug in the Chrome extension where addresses for the wrong domain were shown in the popover, that's now been fixed!
Feel free to leave any thoughts or questions on this update here!