[Bug]: Conditions mixup when deleting one rule, button not changing to save

⚠️ This issue respects the following points: ⚠️

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

Bug description

When removing one existing conditions in a Flow rule, we have disruption in the UI. Instead of disappearing and the Active button turning to Save, the rule name and matcher elements from below move up, and the Active button stays as is.

But, it is clickable and will save the definition, upon a reload the rule is as intented. So it is "only" an user interface issue.

https://github.com/nextcloud/server/assets/2184312/7bbc71d9-1243-4c94-8142-3a3f926d9774

Steps to reproduce

1. Have a flow rule with at least two conditions
2. Remove the first one, observe the described behavior
3. Also observe that Active button did not change to Save (which it would do if you add a condition)
4. Hit the Active button
5. Reload the page

Expected behavior

The UI interface actually shows the intended state, i.e. the removed condition disappears and Active button turns into Save.

Installation method

None

Nextcloud Server version

28

Operating system

None

PHP engine version

None

Web server

None

Database engine version

None

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

None

Are you using the Nextcloud Server Encryption module?

None

What user-backends are you using?

• Default user-backend (database)
• LDAP/ Active Directory
• SSO - SAML
• Other

Configuration report

No response

List of activated Apps

No response

Nextcloud Signing status

No response

Nextcloud Logs

No response

Additional info

No response

Start by reproducing the issue in the Flow rule UI on Nextcloud Server 28 with a rule containing at least two conditions. Trace the frontend handling for removing the first condition and updating the Active/Save button state. Done means the condition disappears immediately and the button changes to Save before reloading.