[Bug]: Login dialog is broken on Windows

[Molitvan]

⚠️ Before submitting, please verify the following: ⚠️

• This is a bug, not a question or a configuration issue.
• This issue is not already reported on Github (I've searched it).
• Nextcloud Server and Desktop Client are up to date. See Server Maintenance and Release Schedule and Desktop Releases for supported versions.
• I agree to follow Nextcloud's Code of Conduct

Bug description

The login dialog does not work on Windows. What I mean by that is that the buttons for copying or opening the login link do nothing, which makes it impossible to log in.

I found a couple of similar issues, but they're years old at this point and none of them was for Windows.

Steps to reproduce

1. Open a new installation of the Nextcloud client for Windows
2. Enter your server URL
3. Try clicking on the copy link or open browser buttons
4. Notice how they don't do anything

Expected behavior

When clicking the copy link or open browser buttons, the link should be copied to clipboard or opened in the default browser respectively.

Which files are affected by this bug

N/A

Operating system

Windows

Which version of the operating system you are running.

Windows 11

Package

Official Windows MSI

Nextcloud Server version

31.0.1

Nextcloud Desktop Client version

3.16.2

Is this bug present after an update or on a fresh install?

Fresh desktop client install

Are you using the Nextcloud Server Encryption module?

Encryption is Disabled

Are you using an external user-backend?

• Default internal user-backend
• LDAP/ Active Directory
• SSO - SAML
• Other

Nextcloud Server logs

Additional info

No response

[nilsding]

I cannot reproduce this with 3.16.2 on Windows 11 -- the buttons work as they should here

can you share the logs? (should be in %appdata%/Nextcloud/logs)

[Molitvan]

Sorry about late reply. I checked the logs and it's complaining about the auth URL not starting with https. I understand that https being a requirement is a good thing, but users should at least be notified somehow about that being the case.

[nilsding]

Can you please paste the mentioned logs here?

(In this case it's fine for me if you replace the hostname with a placeholder -- as long as the URI scheme, port (if any), and paths are still present)

[joshtrichards]

Sorry about late reply. I checked the logs and it's complaining about the auth URL not starting with https. I understand that https being a requirement is a good thing, but users should at least be notified somehow about that being the case.

If the one you're seeing is this one:

desktop/src/gui/creds/flow2auth.cpp

Lines 237 to 240 in 1b08e9c

	if (_enforceHttps && !isHttps()) {
	qCWarning(lcFlow2auth) << "Returned server url | poll endpoint does not start with https";
	emit result(Error, tr("The returned server URL does not start with HTTPS despite the login URL started with HTTPS. "
	"Login will not be possible because this might be a security issue. Please contact your administrator."));

Then the problem is that there is both https and http being used, which indicates a config problem. Likely either overwriteprotocol and/or trusted proxy configuration.