#30079 issue: cloning an arena or workspace model from the admin Models settings leaves Base Model empty

Before Submitting

I searched open and closed issues and discussions for an existing report.
I checked whether this is already fixed on the dev branch or latest source.
I understand that maintainers want a well-written issue before any code pull request.
I am using the latest available version of Open WebUI for my install method.
This is not a security vulnerability.

Installation Method

Git Clone

Open WebUI Version

dev at 58b36765a7c20f5943a3180bd289de48876d0878

Operating System

Ubuntu 26.04.1 LTS

Browser

Firefox 155.0

Ollama Version

0.34.0

Summary

In the admin Models settings, Clone on an arena model or on a workspace model opens the new model form with "Base Model (From)" empty. The clone cannot be saved until a different base model is picked, so it no longer matches the model it was cloned from. Clone on the same workspace model from Workspace, Models opens with the original base model selected.

Expected Behavior

Clone in the admin Models settings opens a form that can be saved as it is, the same way Clone on a regular model does. A workspace model's clone keeps the base model of the original, as it does when cloned from Workspace, Models.

Actual Behavior

The form opens with "Base Model (From)" showing the placeholder "Select a base model (e.g. llama3, gpt-4o)" for both an arena model and a workspace model. For the arena model, clicking Save & Create shows the toast "Base Model is required." and nothing is created.

Steps to Reproduce

Arena model:

Go to Settings, then Evaluations under Admin, turn on Arena Models, add an arena model, and save.
Go to Models under Admin, open the menu on that arena model, and click Clone.
The form opens with "Base Model (From)" empty.
Click Save & Create. The toast "Base Model is required." appears.

Workspace model:

Go to Workspace, Models, and create a model on any base model.
Go to Settings, then Models under Admin, open the menu on that workspace model, and click Clone.
The form opens with "Base Model (From)" empty.
For comparison, click Clone on the same model from Workspace, Models. That form opens with the original base model selected.

Logs, Screenshots, and Config

The cloned arena model with "Base Model (From)" empty after clicking Save & Create:

The Clone option on the arena model in the admin Models settings:

A workspace model cloned from Workspace, Models, which keeps its base model:

I did not capture browser console or server logs.

Additional Information

Anchored to 58b36765a7c20f5943a3180bd289de48876d0878.

Clone in the admin Models settings always sets the clone's base model to the model being cloned. That was written for regular models when this option was added in b88f829dbb76842604b0c898be8023b0f40daeab (2025-11-21). https://github.com/open-webui/open-webui/blob/58b36765a7c20f5943a3180bd289de48876d0878/src/lib/components/admin/Settings/Models.svelte#L637-L647

The model editor does not allow arena models or workspace models as a base model. It leaves them out of the list, and clears a base model that points to one when a new model's form loads. So the clone's base model is cleared, and saving stops at the base model check. https://github.com/open-webui/open-webui/blob/58b36765a7c20f5943a3180bd289de48876d0878/src/lib/components/workspace/Models/ModelEditor.svelte#L227-L248 https://github.com/open-webui/open-webui/blob/58b36765a7c20f5943a3180bd289de48876d0878/src/lib/components/workspace/Models/ModelEditor.svelte#L517-L531 https://github.com/open-webui/open-webui/blob/58b36765a7c20f5943a3180bd289de48876d0878/src/lib/components/workspace/Models/ModelEditor.svelte#L311-L316

Workspace models reach this menu because the admin Models settings list them since ccbb3303f2ec5db0b16573bbb665a12f6764da66 (2026-08-22). Clone in Workspace, Models copies the model as it is, keeping its base model: https://github.com/open-webui/open-webui/blob/58b36765a7c20f5943a3180bd289de48876d0878/src/lib/components/workspace/Models.svelte#L211-L219