Error if german "Umlaute" are in file name

[THS-on]

Hello,
I have some issues with files that have the letters "ö,ä or ü" in it. Tested with Firefox and Chrome using richdocuments 1.12.3 and LibreOffice online 2.1.0 (git hash: 0a8d112).

Error in LibreOffice online logs

kit-22833-23282 14:00:46.239638 [ lokit_164 ] ERR  Failed to load: file:///user/docs/22833/empf%C3%A4nger.odt, error: Unsupported URL <file:///user/docs/22833/empf%C3%A4nger.odt>: "type detection failed"| kit/Kit.cpp:1184
kit-22833-23282 14:00:46.239800 [ lokit_164 ] ERR  Failed to get LoKitDocument instance.| kit/ChildSession.cpp:347

Is this really an issue in richdocuments or is it in LibreOffice online?

Steps to reproduce

1. Create a file with the name "empfänger.odt"
2. Try to open it
3. Get an error message like this: "Das Laden des Dokuments ist fehlgeschlagen. Bitte vergewissern Sie sich, dass der Dateityp unterstützt und die Datei nicht defekt ist, und versuchen Sie es dann erneut."

Expected behaviour

The document opens normally.

Actual behaviour

Error message:

Das Laden des Dokuments ist fehlgeschlagen. Bitte vergewissern Sie sich, dass der Dateityp unterstützt und die Datei nicht defekt ist, und versuchen Sie es dann erneut.

Server configuration

Operating system: Debian 8

Web server: Apache/2.4.10 (Debian) (apache2handler)

Database: mysql 5.7.18

PHP version: 5.6.30-0+deb8u1

Nextcloud version: 12.0.0 - 12.0.0.29

Where did you install Nextcloud from: Source

Signing status:

Are you using external storage, if yes which one: files_external is disabled

Are you using encryption: no

Client configuration

Browser: Mozilla/5.0 (X11; Linux x86_64; rv:53.0) Gecko/20100101 Firefox/53.0

Operating system: Linux

[THS-on]

Only my version was affected. I've tested it with the latest official Version and it's working.
LANG=C.UTF-8 has to be set as environment variable.

[fwolfst]

Where and how did you change the locale? In the Collabora docker container?

[THS-on]

@fwolfst this installation was compiled from source and ran in Debian VM. I don't have that setup anymore, but I think I changed the locale of the vm or exported LANG=C.UTF-8 in the systemd service.