Add support for Internationalised Domain Names (IDNs) (in Firefox)

I have a self-hosted instance of Bitwarden under an Internationalised Domain Name (IDN), aka “umlaut domain”, which contains special characters like “ä, ö, ü”, etc.

These domains are then encoded into punycode, so for example, a domain name like “bücher” is encoded into " xn–bcher-kva". The former domain name doesn’t work if I enter it into the Firefox extension (2025.2.0) on LibreWolf (136.0-2), but the latter works.

It would be great to add support for such domains, so that users can type the internationalised name instead of having to enter the cryptic encoded name.

By the way, I love Bitwarden, thank you very much for creating this wonderful software!

Out of curiosity: would “bücher” work with the desktop app and mobile app? (I mean… is IDN support only missing in the browser extensions?)

I just tested it on 2025.2.1 on Linux Desktop, this works.

Also on Android on version 2025.2.0 this works.

As far as I can tell, only the browser plugins seems affected.

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Thanks for the tests!

I just wanted to ask whether it’s only the Firefox extension, as you stressed that, or if it’s also the “Chromium” extensions… and then I decided to search on GitHub. There is an open bug report:

PS: Welcome to the forum! (Sorry, I forgot that!)