Open graph image not displaying unsupported media type

[dustinmatlock (Dustin)]

@codinghorror

No repro, works fine on my instance (self-hosted)?

I’m hosting on Linode. Had to install the aufs module. Here’s what I followed:

Install Docker with AUFS on Linode

The 30-minute Discourse installation guide assumes you’ll be using Digital Ocean and makes no mention of an important requirement for Docker: If you use another hosting provider, you should really make sure that a Linux kernel feature called “AUFS” is supported. Docker not using AUFS can cause terrible pain. If you want to use Linode, here’s how to enable AUFS support in Ubuntu (for other OSes, refer to Linode’s guide and update the instructions below accordingly: Create the Linode and pic…

On Facebook’s tool it works perfect. I only can’t figure out why the image doesn’t show on Slack.

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