Steps to capture plugin logs.
1. Go to System -> Logging and Profiling.
2. Click on Configure in Default Loggers section.
3. Enter com.miniorange.oauth in package field and select Debug in Logging Level. Click on add.
After these steps, perform single sign-on again to record logs. Then download support zip using these steps,
1. Go to System -> Troubleshooting and support tools.
2. Proceed to create support zip.
3. Click on Customize Zip, keep only Jira Application Logs option selected and Save settings.
4. Click on Create zip and then Download zip.