Please check the following for smooth use of the flex service.
Compatibility Self-Check Page
If file uploads fail or screens don't load while using flex, it may be due to company network settings or security programs (firewalls, ad blockers, etc.) preventing smooth access to flex.
You can check whether your current environment supports smooth use of flex on the compatibility self-check page below.
You can check the following through this page.
Whether your browser meets the flex supported version
Whether communication to the flex service is working properly in your network environment
If the connection check is not normal, you can copy the external access allowlist URLs and send them to your internal network team.
Supported Web Browsers
Browser | Supported Version |
Chrome | 109 or higher |
Chrome (Android) | 140 or higher |
Safari (Mac) | 18.5 or higher |
Safari (iOS) | 15.6 or higher |
Edge | 138 or higher |
Firefox | 141 or higher |
Samsung Internet | 28 or higher |
- Browser compatibility settings are managed with variable values. Therefore, compatible versions may increase over time.
- The table above is based on minimum supported versions as of 2025.09.30.
Network
If your company's internal network firewall manages an external access allowlist (whitelist), please register the following.
Domains
flex product:
*.flex.teamFile upload:
flex-prod-storage.s3.ap-northeast-2.amazonaws.comAddress search:
www.juso.go.krSupport tool:
*.intercomcdn.com,*.intercom.io,*.intercomassets.com,intercom-sheets.com,intercom.help
Network port:
443HTTP method:
GET,POST,PUT,DELETE,PATCH,OPTIONS,HEAD
flex Mobile App
Android
9.0 Nougat or higher
iOS
16.4 or higher