Having the same issue, I’m using Cloudron to run N8N and the odd part is that on 2 N8N instance I don’t have this problem (they all are same version of N8N)
And on 1 other N8N instance I have this error, with the Mastodon Community Node.
Not sure what I can do to debug more and find out.
NodeApiError: UNKNOWN ERROR - check the detailed error for more information
at Object.mastodonApiRequest (/app/data/user/.n8n/nodes/node_modules/n8n-nodes-mastodon/nodes/Mastodon/Mastodon_Methods.ts:195:9)
at Object.create (/app/data/user/.n8n/nodes/node_modules/n8n-nodes-mastodon/nodes/Mastodon/Mastodon_Methods.ts:88:35)
at Object.execute (/app/data/user/.n8n/nodes/node_modules/n8n-nodes-mastodon/nodes/Mastodon/Mastodon_Methods.ts:19:42)
at Object.execute (/app/data/user/.n8n/nodes/node_modules/n8n-nodes-mastodon/nodes/Mastodon/Mastodon.node.ts:41:48)
at Workflow.runNode (/app/code/node_modules/n8n-workflow/src/Workflow.ts:1270:42)
at /app/code/node_modules/n8n-core/src/WorkflowExecute.ts:938:44
at processTicksAndRejections (node:internal/process/task_queues:95:5)