Physical LG Android 5.1.1 testing found Chrome 43 could decode gzip but failed on the bootstrap's arrow syntax. Use ES5 functions and Promises while preserving retries, version refresh, and optional abort handling. Keep Google Zopfli gzip compression at 1,000 iterations.
Verified the flashed V4.3 through its WiFi link using the real Android browser: bootstrap and main page gzip responses completed, settings loaded at 910.525 MHz, and no JavaScript or transfer errors were reported. Add a loader syntax regression and document legacy browser support.