[PM-40981] WebAuthn Mobile Connector Page Not Working

[WilliamWsyHK]

Steps To Reproduce

1. Enable account with MFA / Security Key on Desktop
2. Use Bitwarden Password Manager for Android
3. Login as usual
4. Proceed WebAuthn page with browser (doesn't matter between embedded or standalone browser)
5. Wait for page to load in the browser

Expected Result

The WebAuthn Mobile Connector page will render correctly with the text on blue button

Actual Result

No text on blue button, in addition to no response after pressing the blue button.

The same link from the android browser is copied to desktop browser to test but same behavior observed.

Screenshots or Videos

Additional Context

Page: https://vault.bitwarden.com/webauthn-mobile-connector.html?data=<redacted>&parent=https%3A%2F%2Fbitwarden.com%2Fwebauthn-callback&client=mobile&v=2&deeplinkScheme=https

This is not directly related to #6313 (as the referenced issue about the URL scheme not working) but mentioned here for easy reference.

Build Version

2026.6.0, 2026.6.1, 2026.7.0

What server are you connecting to?

US

Self-host Server Version

No response

Environment Details

© Bitwarden Inc. 2015-2026

版本：2026.6.1 (21713)
📱 OnePlus PLR110 🤖 16@36 📦 prod
🧱 commit: e5ee43f
💻 build source: bitwarden/android/actions/runs/28253991408/attempts/1
🦀 SDK: 3.0.0-7536-159aed97
🌩 Server: 2026.6.2 @ US

© Bitwarden Inc. 2015-2026

版本：2026.7.0 (21756)
📱 OnePlus PLR110 🤖 16@36 📦 prod
🧱 commit: 36c892e
💻 build source: bitwarden/android/actions/runs/29108828120/attempts/1
🦀 SDK: 3.0.0-7673-101364a4
🌩 Server: 2026.7.1 @ US

Issue Tracking Info

• I understand that work is tracked outside of Github. A PR will be linked to this issue should one be opened to address it, but Bitwarden doesn't use fields like "assigned", "milestone", or "project" to track progress.

[bitwarden-bot]

Thank you for your report! We've added this to our internal board for review.
ID: PM-40981

[pamperer562580892423]

Looks like a duplicate of #7211 There is new information - see this comment: #7212 (comment)

[liakoulee]

Looks like a duplicate of #7211

Not a duplicate anymore because my issue (7211) got closed as "not able to reproduce by the tech guy".

And yes, I'm still facing this issue as well.

[ant-be]

Hi there,

Similarly to my colleague on the other thread(7211), unfortunately was not able to reproduce this issue on mobile/android. This has been escalated for further investigation. If you have more information that can help us, please add it below.

Thank you!

[liakoulee]

I have found the cause of the issue with the help of ChatGPT and got the button to load. Pass this to the devs.

After testing the js script codes back and forth with ChatGPT on the Webauthn page we found that the button can't render and we reached a point where the Greek text(my phone's language) in the script and utf encoding was mentioned and after a while I thought to try and change the BW app language from Auto(system language) to English and voila. Button loaded and functions as it should without issues, just in English.
So, anyone else facing this issue and have a different language set in the app, try English.

Gpt's clues about the issue if they're any help to devs:
The Bitwarden app is generating malformed JSON/Base64 when localized strings contain Greek characters.
The connector's b64Decode() isn't correctly decoding UTF-8 for non-ASCII text.
There's a bug specifically in the Greek localization (for example, a bad quote, % sequence, or encoding issue in one of the translated strings).

[WilliamWsyHK]

Wow, @liakoulee is correct, as I am using Traditional Chinese, and switching to English makes the page render the button correctly.

[djsmith85]

@bitwarden/team-auth-dev I personally haven't tried to repro, but there might be something to this, with how it's trying to find elements via document.getElementById (header, webauthn-button) and not doing any defensive programming. For the header (which is only present on some pages) and the button, wouldn't it be possible to add a default text, that only gets overridden in case it is provided?