Amazon Q Chat has stopped working in VS Code, even though Inline Chat Works

After latest update, Amazon Q has stopped working in VS Code. Chat Window does not open and keeps loading forever. Even though connection is valid and inline chat is working.

2025-05-08 19:35:07.564 [info] lsp: trying local "AmazonQ" manifest...
2025-05-08 19:35:11.289 [info] initialized 'submitFeedback' command with default feedback id: Amazon Q
2025-05-08 19:35:11.339 [info] auth: Connection is valid: 105c288a-b8d2-4a83-8043-97dc17391f57
2025-05-08 19:35:11.339 [info] auth: Updating connection state of 105c288a-b8d2-4a83-8043-97dc17391f57 to valid
2025-05-08 19:35:14.372 [error] notifications: Failed to fetch at endpoint: https://idetoolkits-hostedfiles.amazonaws.com/Notifications/VSCode/startup/1.x.json, err: TypeError: Cannot read properties of undefined (reading 'headers')
2025-05-08 19:35:25.293 [error] CodeWhisperer: Error when fetching feature configs TimeoutError: Connection timed out after 120000ms
2025-05-08 19:35:25.605 [error] CodeWhisperer: Error when fetching feature configs TimeoutError: Connection timed out after 120000ms
2025-05-08 19:35:47.383 [error] notifications: Failed to fetch at endpoint: https://idetoolkits-hostedfiles.amazonaws.com/Notifications/VSCode/startup/1.x.json, err: TypeError: Cannot read properties of undefined (reading 'headers')
2025-05-08 19:36:20.444 [error] notifications: Failed to fetch at endpoint: https://idetoolkits-hostedfiles.amazonaws.com/Notifications/VSCode/startup/1.x.json, err: TypeError: Cannot read properties of undefined (reading 'headers')
2025-05-08 19:36:53.442 [error] notifications: Failed to fetch at endpoint: https://idetoolkits-hostedfiles.amazonaws.com/Notifications/VSCode/startup/1.x.json, err: TypeError: Cannot read properties of undefined (reading 'headers')

Reproduce the failure in the Amazon Q Chat window in VS Code after the latest update, then inspect the supplied logs, especially the feature-config timeouts and notification fetch failures. Done means the Chat window opens and loads while the existing inline chat and valid connection continue to work; no source file or test is identified in the report.

Written by the indexing model from the issue text.