Video playback broken - "index out of bounds, the container is empty"
Since a recent-ish commit, video playback has been broken with clients receiving a 502:

```
An error has occured in one of your routes.

Detail: fatal.nim(49) sysFatal
asyncfutures.nim(390) read
asyncfutures.nim(390) read
index out of bounds, the container is empty
```

(by the way, there's a typo in this stacktrace, it's "occurred" not "occured")

I started to notice this stacktrace in the nitter logs, but I didn't know what caused it, and nothing seemed broken so I ignored it, but it was reported to me today by @B0pol that video playback was broken: this is what is causing it.

---

Running latest master

Nim 1.4.8 (I suspect this is why you don't encounter the issue since you seem to only test on latest)

Nimble 0.013.1

Both video proxy enabled, or disabled are affected.

Example URL: https://nitter.pussthecat.org/elonmusk/status/1480326831031173124