Authorizing for crossposting results in a 502 on micro.blog
Micro.blog Help Center [Unofficial]
June 13, 2026
Connecting a Mastodon account on signers.online (Mastodon 4.6.0-rc.1+glitch) fails: micro.blog’s /mastodon/callback receives the OAuth authorization redirect but never POSTs to /oauth/token to redeem the code.
On signers.online’s side the app is registered correctly (redirect_uri https://micro.blog/mastodon/callback, scopes read write follow), /oauth/authorize returns 302 with a valid code in ~30 ms, and /oauth/token is healthy.
Across ~10 attempts signers.online issued 10 authorization codes; micro.blog redeemed exactly one, and that token was then never used for any API call.
The callback appears to error (502) before redeeming the code.
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