Selecting Arabic on the FTU screen makes the list of languages change directions, but the next/previous buttons at the bottom of the screen don't change their direction.
There is some problem with webcomponents and we can't overide the css rules of them with `html[dir="rtl"]` ... I ping Vivien in Bug 992249 to see if he knows something
Pavel, that's OK. I think that we are not yet sure if this is something we want to do. Let's just get an assessment of this work and decide if it is something we should or should not do. Thanks!
The problem here is not related with this Bug only but is related with web components at all Simple Case: if we have `text-align: left` somewhere in a web component we can't override this style and this will be a problem for RTL support.
Mass Edit: adding the [rtl-meta]
Test case has been added in moztrap: https://moztrap.mozilla.org/manage/case/15449/