If I have multiple tabs/windows open in Firefox, which of them can potentially be recording my keystrokes?

Question

Let's say, in Firefox, I have two windows open (W1 and W2), and each has two tabs (e.g. W2.T1 = second window, first tab). On each window, T1 is the tab that's in focus. Currently, my computer has W1 highlighted/focused on.

My question is, when I start typing something into W1.T1 (e.g. a password), can any of the other windows/tabs listen to my keystrokes?

What about if I'm typing something into Microsoft Word, can any of the Firefox tabs open in the background listen to my keystrokes?

And lastly, I have the Bitwarden Plugin for Firefox. When I click on the Bitwarden plugin and enter my master password (to unlock my password vault), can the tab I currently have open listen in on those keystrokes?

Answer 1

My question is, when I start typing something into W1.T1 (e.g. a password), can any of the other windows/tabs listen to my keystrokes?

No. The exception is if any of the other tabs are connected to the same host.

What about if I'm typing something into Microsoft Word, can any of the Firefox tabs open in the background listen to my keystrokes?

No. Regardless of whether the Firefox tabs are in the foreground or background, they cannot listen to your keystrokes entered in another application.

And lastly, I have the Bitwarden Plugin for Firefox. When I click on the Bitwarden plugin and enter my master password (to unlock my password vault), can the tab I currently have open listen in on those keystrokes?

No. Again, regardless of whether the Firefox tabs are in the foreground or background, they cannot listen to your keystrokes entered into an extension. Each extension runs in a separate security context.