Putting generated addresses into forms... I would do that manually.
If I really would do that multiple times a day (But who signs up for services so often?) I would use a bookmarklet for it.
Bookmarklets are way less intrusive than extensions. And have other usability advantages. I can nicely put them into my bookmarks for example.
But it still feels wrong to me. Instead of giving company A their email, you are suggesting people give company B full access to all their browsing data. The "Trust us we are the good guys" approach just does not click with me.
"Why do you need my house keys to deliver mail?"
"So we can put packages inside the house in case it's raining hard and you are not at home."
"That's OK, I have a good porch and would rather you put everything not fitting in the mailbox there"
"Studies show that users prefer dry packages and may be concerned with theft. We need this in order to provide secure delivery in all conditions, take it or leave it"
No: https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/Web...
> Use the `optional_permissions` key to list permissions that you want to ask for at runtime, after your extension has been installed.
That you promise to behave well does not change that. It is the "Trust us" argument again. If we could trust companies, we could give them our real emails.
I'm assuming you realize that there is more than one company, and that one can trust different companies to different extents. I trust DDG more than I trust most other companies. I trust DDG more than I trust Amazon, and I've given Amazon my email--a decision I sometimes regret!
But DDG proposes "Trust us with all your browsing data, including your private emails, your bank statements, all your passwords, everything you read and write rather than manually type the temp email". To me that seems pretty extreme.
I suggest that DDG proposes, "Trust us with access to many things, most of which we promise we won't even look at, none of which we will ever keep." Given that the extremeness is the result of browser makers, I think DDG has earned my trust. Your mileage may vary.