KA Hearth

A small blog where Matthias posts thoughts on things happening around Khan Academy. About Me

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KA censoring links in Bio

First brought to my attention by Jett on Discord, on April 24th, KA started censoring links in user bios. A link in your bio ends up being replaced with ***. This makes sense in context of my previous post.

KA started hiding comments with offsite links in an attempt to stop a certain user spamming links to a Google Doc with neo-nazi propaganda. This was easily circumvented by a comment, “check the link in my bio.” KA’s reply is to censor links in the bio.

I think this is suprisingly effective. It can be bypassed of course, either by replacing periods in URLs with spaces, or by linking to a KA program with an offsite link. In the later case, of course, a KA program can be hidden in the event that you’re linking to content that wouldn’t be allowed.

Unfortunetly, even KA links in your bio or other strings that looks like URLs (e.g. “node.js”) get censored. So you can’t link to your new KA program in your bio.

It’s worth pointing out that this censoring happens on the client side, so you can actually save a bio with a link; and you get the link from the KA API. This means it’s possible for something like the KA Extension to undo KA-censoring’s for its users. (I don’t think we will; there’s not really a reason to if people don’t have links in thier bios.)

I found a very easy way to bypass this when analyzing KA’s censoring code. I’ve reported this to Zendesk so that KA can fix it. I’ll share it publically in a couple of months if links to a certain Google Doc are no longer an issue, and if KA hasn’t fixed it by then. Of course, once the pressing issue is resolved, it is my hope that KA will seriously consider undoing this change and allowing links.

Update. The bypass I mentioned has been fixed. Follow up post.