Of course they can communicate with each other, they're extensions, not web pages. Firefox extensions are Javascript CSS and XUL so I don't think that's obviou

Of course they can communicate with each other, they're extensions, not web pages. Firefox extensions are Javascript CSS and XUL so I don't think that's obvious. I think it's entirely reasonable to assume that they might be sand boxed and have no awareness of each other. Is it one instance of the toolbar per "page-opened" event? Is it one instance per window? What I was describing was a way to stay under the limit without having centralized state-aware rate-limiting code. If that's possible, then yeah sure, do it that way. It's obvious the limiting is rate based, otherwise this would never have happened, so if it is rate based then the toolbar could pace itself to below that rate. It's not obvious to me. I think the issue is that the OP opens 50 tabs simultaneously after a crash and each window opens a connection to google without a rate limit of any kind. My idea was a way to do it without a centralized state.