UXP plugin validation failed: manifest version not supported

Direct Resolution

For Premiere Pro 24.x, the minimum accepted manifest version for unsigned UXP panels is v6. To resolve the validation error, update your manifest.json file to specify "manifestVersion": 6.

Technical Explanation

The "manifest version not supported" error occurs when the manifestVersion integer falls outside the range accepted by the UXP runtime embedded in the host application. While developer-mode flags bypass the requirement for a digital signature (allowing local-only functionality without Adobe I/O credentials), they do not relax the manifest version check. The runtime still requires a supported version to determine which API surface and security permissions to apply to the plugin.

Version Compatibility and Forward Path

• v6: This is the baseline for the 23.x and 24.x lines. It provides the necessary compatibility for minimal panels and basic UXP API access.
• v7: You should only target v7 if your plugin requires specific APIs introduced in that version. For a minimal local-only panel, v6 is sufficient and maintains broader compatibility across the current version range.
• v8+: Until officially documented as a requirement for a specific Premiere Pro release, targeting v8 may trigger the same validation error in current 24.x runtimes.

Implementation and Verification

Follow these steps to verify local-only functionality:

1. Modify your manifest.json:

   {
     "manifestVersion": 6,
     "id": "your.plugin.id",
     "version": "1.0.0",
     ... 
   }

2. Ensure Enable Extension Developer Mode is toggled on in Preferences > Plugins, or launch Premiere Pro with the -DeveloperMode flag.
3. Load the plugin via the Adobe UXP Developer Tool or by placing the folder in the local developer plugins directory.
4. Check the UXP console to confirm the panel loads without the validation error.

Diagnostic Note: If the error persists after updating to v6, please specify if you are using a Beta build of Premiere Pro, as Beta runtimes may shift the supported version range upward.