We have this problem too.

Tool Manager: Installing https://github.com/tasmota/esptool/releases/download/v3.2/esptool-v3.2.zip
Error: Got the unrecognized status code '503' when downloaded https://github.com/tasmota/esptool/releases/download/v3.2/esptool-v3.2.zip
Error: Process completed with exit code 1.

My guess is that if you logged the rest of the response you’d see that you hit an egress limit.

  <a href="https://github.com/github/feedback/discussions/8535" target="_blank" rel="noopener nofollow ugc">GitHub</a>

Release asset failing to download due to account egress limit · Discussion...

Hey all! We've seen this strange error when running terraform a few times today in our CI/CD environments, and it appears be saying that the release asset cannot be downloaded from github due t...

I can’t find any particular documentation about this limit. There are plenty of references to it as a thing and there are plenty of places where GitHub says that it reserves the right to enforce additional usage limits.

Since electron isn’t you, you could file an issue in their tracker – I don’t see one currently:

  <a href="https://github.com/electron/electron/issues?q=is:issue%2Bis:open%2B503" target="_blank" rel="noopener nofollow ugc">GitHub</a>

Issues · electron/electron

Build cross-platform desktop apps with JavaScript, HTML, and CSS - Issues · electron/electron

But, frankly, the fact that you are seeing this “a lot” tells me you’re doing something wrong.

You shouldn’t be downloading the same resource repeatedly. Save it somewhere! The act of downloading a resource is not free, it costs someone something.

The error is not repo related - it is GitHub related. 503 means Service Unavailable.

Read more here: 503 Service Unavailable - HTTP | MDN