I discuss _privacy_ issues.
In the excerpt I quoted, https://libreplanet.org/wiki/Libre_Browsers_Libre_Formats#Browsers_that_might_seem_free.2C_but_are_not is not about privacy. At all. Just a precision in my post: not all Firefox derivatives do not suffer from the freedom issues that the link points out. But Abrowser and IceCat are OK: 100% free as in freedom.
