[jasode]

Ok, fair enough. Before I wrote my comment, I did perform a "view source" to search for "ad-free internet" and it wasn't found. However, if one uses F12 Developer Tools to inspect the DOM, it does have:

  "<title>Ad-free Internet by Firefox</title>"

It's interesting that that phrase is not visibly used and the big bold text people actually see just says "Support the sites you love, avoid the ads you hate".

EDIT to the replies: Yep got it. I can't see the title text on any tabs because they're too narrow when I have 50 tabs open.

[dewey]

It's used in the tab / window heading which is pretty visible I'd say.

[matt_morgan]

It's the page title. It appears e.g. in the tab heading (but yours may be very small).

[luckylion]

Mine are also very narrow, but yeah, it's weird that they only set it with JS.

  <title data-react-helmet="true"></title>

is in the source.

[mariushn]

In this case, I think Firefox is disingenuous.