The vendor you need (Siemens SCL, Rockwell L5X, Fanuc TP, CODESYS ST...) is missing from the Translate to Target Language picker.
Each target is contributed by its own AutomationView extension. If the matching extension is not installed or is disabled, the target has no provider.
codesys, siemens, rockwell, fanuc).Check the extension is enabled in the current workspace - it may be disabled per workspace even if installed globally. If the target is still missing, an API version mismatch (shown as a warning in the Extensions view) means AutomationView and the plugin need to be on compatible versions.