Automatically sends repeated requests to webserver when a link is sent in chat

There's some very strange behaviour when sending links in chat in Windows 10.

When merely pasting a link into the chat box (Without sending), a GET request is sent to the URL, along with a GET request to /apple-touch-icon-icon.png.

When sending the link into the chat it results in the request being repeated indefinitely in precisely 5 second intervals. The requests continue to be sent even after the client is closed, both from the window "X", and from the system tray. Only by killing all keybase processes in Task Manager do the requests stop.

Here's some data I collected from a flask application I used to record the requests ("wahed" is just the name of the route I used for testing and is unrelated):

Request header followed by the request body (empty):

POST /wahed HTTP/1.1 200 -
Host: <removed>:1337
User-Agent: Mozilla/5.0 (compatible; Keybase; +https://keybase.io)
Accept: */*
Upgrade-Insecure-Requests: 1
Accept-Encoding: gzip
Connection: keep-alive

No source files or tests are named. Start by reproducing the link-paste and link-send behavior in the Windows 10 desktop chat client, then trace the link-preview request handling and shutdown behavior. Done means requests are not repeated indefinitely and stop when the client closes.