Description: We have encountered a significant performance issue with NativeMessaging API in Firefox when an extension communicates with a native application. In scenarios where many objects must be enumerated (e.g., ~458 certificates), Firefox is dozens of times slower than Chromium-based browsers. Environment: Firefox (latest stable, reproduced in 2025) Windows 11 x64 Same machine and same native plugin tested in Chrome, Edge, Yandex Browser Steps to Reproduce: Create a WebExtension that communicates with a native application via NativeMessaging. Perform enumeration of a large number of objects (≈ 450–500). Measure execution time in Firefox vs Chromium. Actual results: Firefox: enumeration of 458 objects takes ~2 min 30 sec Chromium/Edge/Yandex Browser: enumeration of the same 458 objects takes ~5 sec Additional tests: Round-trip time (RTT) for a single message: Firefox: ~73.7 ms Chromium: ~0.3 ms Because the extension and the plugin exchange a large number of messages, this performance gap becomes critical. Expected results: NativeMessaging API in Firefox should perform at a level comparable to Chromium browsers, so that extensions relying on heavy message exchange remain usable. References: Bug 1288912 – Native messaging performance is extremely poor Although this bug is marked as resolved, performance testing still shows a major discrepancy in the current versions of Firefox. Question: Is there any ongoing work or plan to optimize the implementation of NativeMessaging API in Firefox to address this performance issue?