"Choose what to sync" unresponsive

### ⚠️ Before submitting, please verify the following: ⚠️

- [x] This is a **bug**, not a question or a configuration issue.
- [x] This issue is **not** already reported on Github (I have searched for it).
- [x] Nextcloud Server and Desktop Client are **up to date**. See [Server Maintenance and Release Schedule](https://github.com/nextcloud/server/wiki/Maintenance-and-Release-Schedule) and [Desktop Releases](https://nextcloud.com/install/#install-clients) for supported versions.
- [x] I agree to follow Nextcloud's [Code of Conduct](https://nextcloud.com/contribute/code-of-conduct/)

### Bug description

I select "Choose what to sync" when setting up an account. The menu appears where I can select subfolders. However when I choose OK, nothing has happened, there is no way to proceed and I am stuck at the dialog where I can choose between "Synchronize everything" and "Choose what to sync", without any way to proceed.

### Steps to reproduce

When adding an account, select "choose what to sync". (In my case the situation is that I do not have the storage space for a full sync.)

Select which subfolders to sync and select OK.

The dialog with options "Synchronize everything" and "Choose what to sync" reappears with no checkboxes selected and no way to proceed.

### Expected behavior

After selecting subfolders and choosing OK, I expect to be able to continue setting up my connection.

### Which files are affected by this bug

?

### Operating system

Linux

### Which version of the operating system you are running.

Fedora 44, updates installed

### Installation method

Official Linux AppImage

### Nextcloud Server version

? I cannot access my account

### Nextcloud Desktop Client version

34.0.3daily

### Did this occur after an update or on a clean installation?

Minor version update (i.e. 33.0.0 → 33.0.1)

### Are you using the Nextcloud Server Encryption module?

Yes

### Are you using an external user-backend?

- [ ] Default internal user-backend
- [ ] LDAP or Active Directory
- [ ] SSO - SAML
- [ ] Other

### Nextcloud Server logs

```shell
I don't have this file in my system
```

### Additional info

I am simple end user. There are questions about the server (version number, encryption module etc) here which I do not know how to answer (I did try to find out). Perhaps after I would be able to add my account, which now I cannot do.

Updates are installed automatically so I don't know which update broke Nextcloud.

[nextcloud.zip](https://github.com/user-attachments/files/31943838/nextcloud.zip)

Start by reproducing the account setup flow on Linux using the AppImage, selecting “Choose what to sync,” choosing subfolders, and pressing OK. Trace the dialog behavior when it returns with no selections; done means the selected folders persist and account setup can continue.

Written by the indexing model from the issue text.