The Outlook 365 Add-in encountered an issue where email signatures failed to load promptly for a subset of users. The delay was noticeable when users opened the email composition window, causing a degraded user experience. The issue was reported by multiple users across different regions and was traced back to internal changes in how image URLs are processed within the add-in.
The issue was caused by recent internal changes to the image URL processing logic in the Outlook 365 Add-in. Specifically, a new validation step for image URLs introduced unintended latency when fetching signature images from external servers.