You want to know what the size limit is for a policy trace on the Edge SWG (ProxySG)
Starting in 7.3.21.1 and 7.4.5.1 there is a limit of 10 MB.
Prior releases have a limit of 1 MB in size.
If you are missing information in the policy trace, you may need to limit the scope in what you are tracing.
Example code added to local policy to limit the trace to a particular client IP address <ip addr> and to URL domain of "example.com"
<proxy>
client.address=<ip addr> url.domain=example.com trace.request(yes) trace.destination(trace1)
<ssl-intercept>
client.address=<ip addr> url.domain=example.com trace.request(yes) trace.destination(trace1)
Reference: Use policy tracing to debug access denied errors or website accessibility issues
To open the debug file generated by the policy trace, go to Proxy IP address - https://X.X.X.X:8082/policy. You should see policy trace you named above (trace1)