How to fix “With the current security level configuration, only custom nodes from the "default channel" can be installed.”?

This is due to the latest update in ComfyUI-Manager.

1. Find the config.ini in the File Browser
1. ComfyUI/user/default/ComfyUI-Manager

2. If your manager version is below 3.0, go to ComfyUI/custom_nodes/ComfyUI-Manager
2. Double click on the config.ini, this will open the file in an editor like below and now you can config the manager in whatever way you like by following the params in here.
   GitHub GitHub - ltdrdata/ComfyUI-Manager: ComfyUI-Manager is an extension designed to enhance the usability of ComfyUI. It offers management functions to install, remove, disable, and enable various custom nodes of ComfyUI. Furthermore, this extension provides a hub feature and convenience functions to access a wide range of information within ComfyUI.
1. The following will only work on current/beta version
2. Once you finish editing the config.ini, you need to restart the ComfyUI by clicking the top left “Restart ComfyUI” button (NOT restart the machine).

Related how-to,

See also, https://github.com/comfyanonymous/ComfyUI_TensorRT/issues/6.

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