Embed options on Medium / Embedly are incorrectly cached

🐛 bug report

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Description of the problem

This is a follow-up of the problem described in #6838. I am not sure if this issue is identical or just very similar. Unfortunately my problem seems to persists even though #6838 is closed.

The first time I embed a sandbox with options on Medium, these options are correctly reflected in the embed. However, this no longer works if I embed a second link to the same sandbox, but with different options. A cached embed is displayed, using the old query parameters.

There is no caching issue when visiting the embed link directly (bypassing Embedly). The codesandbox.io/oembed endpoint also doesn't seem to have this problem. I suspect that Embedly strips down all sandbox URLs to a version without query parameters (as this comment had already pointed out) and uses that as some sort of caching key.

Because it's likely (though I'm not 100% sure) this issue is on Embedly's side, I have contacted their customer support about it. It seems like this did seem to help with #6838, so I'm hoping they can again provide a solution. I will let you know if I get a response.

How has this issue affected you? What are you trying to accomplish?

I am trying to embed the same Sandbox in Medium article multiple times, where each embed displays a different file. This issue makes that impossible, as changes to the module parameter are ignored. Instead, all embeds in the article will display the same module.

To Reproduce

1. Generate an embed link with custom options
2. Paste the link in the Medium editor or submit it in Embedly's Embed Code Generator tool
3. Change one of the URL parameters of the embed link
4. Repeat step 2 with the new link

Link to sandbox: link

Note: this is the sandbox I provided to Embedly support, but this issue seems to reproduce with any sandbox.

Your Environment

Start by reproducing the two sandbox embeds through Medium or Embedly, using the linked sandbox and changing a URL option such as module. Compare the direct codesandbox.io/oembed response with Embedly's result; done means distinct query parameters produce distinct embeds, or the issue is confirmed to require Embedly rather than this repository.