I added the Sentry Javascript SDK without any modification or calls beyond Sentry.init(). (int his report I had to change https:// to _ttps:// to avoid the two-links-per-post limit)
Summary
URL: _ttps://sentry.io/api/somenum/store/?sentry_key=mykey&sentry_version=7
Status: 413 Request Entity Too Large
Source: Network
Address: 35.188.42.15:443
Request
POST /api/somenum/store/ HTTP/1.1
Accept: /
Content-Type: text/plain;charset=UTF-8
Origin: _ttps://mysite.com
Content-Length: 329636
Accept-Language: en-us
Host: sentry.io
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_4) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/12.1 Safari/605.1.15
Referer: _ttps://mysite.com/
Accept-Encoding: br, gzip, deflate
Connection: keep-alive
Response
HTTP/1.1 413 Request Entity Too Large
Content-Type: text/plain
Access-Control-Allow-Origin: *
Connection: close
Date: Sun, 31 Mar 2019 01:15:30 GMT
Content-Length: 29
ETag: “5b27f818-1d”
Server: nginx
Strict-Transport-Security: max-age=31536000; includeSubDomains; preload
Query String Parameters
sentry_key: mykey
sentry_version: 7
Request Data
MIME Type: text/plain
Encoding: UTF-8
Request Data: