To the developer of "Run", in case if more browser support is needed:
* "Access-Control-Allow-Origin" header is missing. It's needed for cross-domain requests for some [browsers](https://developer.mozilla.org/ru/docs/Web/HTTP/Headers/Access-Control-Allow-Origin) and by [standards](https://fetch.spec.whatwg.org/#http-access-control-allow-origin) ("play.nim-lang.org" is regarded as a different domain). Firefox logs this: Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at https://play.nim-lang.org/compile. (Reason: CORS header 'Access-Control-Allow-Origin' missing). It can be solved by adding response-header `Access-Control-Allow-Origin: https://forum.nim-lang.org` or `Access-Control-Allow-Origin: *`. * `code` parameter is not sent in requests, only `compilationTarget`, because `code`'s content is retrieved via `innerText`, which was not in standards until last year and is supported by Firefox only from that time. `innerHTML` is long supported and can be used instead, tags then should removed.
