validate layout with users of right-to-left scripts

[cfm]

Description

As part of coordinating (#1304) with Localization Lab the official start of translation of the Client, we should ask any translators working in languages using right-to-left scripts (e.g., Arabic, Hebrew, Persian) for their feedback on the Client's UI/UX in a right-to-left context.

Context

I've successfully tested the display of a translation in a right-to-left script by borrowing securedrop's Arabic translation like so:

(.venv) cfm@ozymandias securedrop-client % git diff
diff --git a/securedrop_client/gui/auth/dialog.py b/securedrop_client/gui/auth/dialog.py
index f0f56aa..7009358 100644
--- a/securedrop_client/gui/auth/dialog.py
+++ b/securedrop_client/gui/auth/dialog.py
@@ -96,7 +96,7 @@ class LoginDialog(QDialog):
         self.password_label = QLabel(_("Passphrase"))
         self.password_field = PasswordEdit(self)
 
-        self.tfa_label = QLabel(_("Two-Factor Code"))
+        self.tfa_label = QLabel(_("Two-factor Code"))
         self.tfa_field = QLineEdit()
 
         self.opacity_effect = QGraphicsOpacityEffect()
(.venv) cfm@ozymandias securedrop-client % cp -Rp ../securedrop/securedrop/translations/ar securedrop_client/locale/
(.venv) cfm@ozymandias securedrop-client % LANG=ar ./run.sh

We can see in this screenshot that (present) Arabic translations are displayed correctly right-to-left. (For the purpose of this cross-project test, we don't care that some source strings are displayed untranslated.) So, upon focus, are the QLineEdit fields. What we don't know is whether the UI (both including and beyond the login dialog) is displayed as right-to-left readers will expect.

These UI/UX changes are beyond the scope of Internews's funding of the translation-oriented work tracked in #239, but they will be essential for meaningful localization of the Client as it is translated into locales including right-to-left scripts.

How will this impact SecureDrop users?

Once the Client is translated into a language that uses a right-to-left script, its layout should be idiomatic for users of those languages and scripts.

How would this affect the SecureDrop Workstation threat model?

No threat implications.

User Stories

As a journalist using a right-to-left script, I want the Client to be laid out according to the text direction of my script, so that I can read and interact with it fluently.

References

• https://forum.qt.io/topic/39218/supporting-right-to-left-languages/5
• https://witekio.com/blog/qt-internationalization-arabic-chinese-and-right-to-left-3/
• https://rtlstyling.com/posts/rtl-styling/
• https://spectrum.adobe.com/page/bi-directionality/
• https://material.io/design/usability/bidirectionality.html#localization (via https://forum.securedrop.org/t/bidirectionality-best-practices-guide/1193)