🐞: Elipsize error strings like: "...<urlopen error timed out>..."

[yozachar]

The network connection was lost after I tried to check of speed. I think it's still reproducible.

1. Connect to a (very if possible) slow network. (just to reporduce)
2. Open Nutty and click on Speed.
3. Click refresh icon on the right.
4. Wait for the error.

Got a very long error:

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Just a design suggestion. After ellipsizing a less verbose error message, you may display it on as a transient message (like toast in android apps).