IGEL OS 11.02 IGEL OS Articles Certificates Deploying Trusted Root Certificates Current: Installing Certificates Manually PDF Download PDF Download page Installing Certificates Manually. Current page Include child pages All pages Installing Certificates Manually Use the Firefox Certificate Manager in order to install web browser certificates; see Installing Web Browser Certificates.Also a USB flash drive can be used for the manual import. Importing SSL Certificates (ICA, RDP, Horizon) Installing Web Browser Certificates ×