v2.5.0（正式版） / Final

绿色免安装，解压即用；从 2.4.x 升级前建议备份 %LOCALAPPDATA%\MegaDownloader\Config\Configuration.xml。2.4.7 及更早版本会收到本次更新提示。
Portable, no install; back up %LOCALAPPDATA%\MegaDownloader\Config\Configuration.xml before upgrading from 2.4.x. Versions 2.4.7 and older will be offered this update.

What's Changed / 本次变更

匿名下载 MEGA 配额专项 + 生产审计三批修复，一句话：配额可预期，失败不静默，卡顿不再来。
Quota handling for anonymous downloads plus three batches of production-audit fixes. In one line: predictable quota, no silent failures, no more UI freezes.

• 配额全局熔断 + 倒计时横幅 / Quota circuit-breaker + countdown banner：509 / -17 归一识别；60 分钟 → 2 小时 → 6 小时递进等待；横幅 + [立即重试] + 状态栏倒计时 + 托盘气泡。Identified by status code 509 / API -17; escalating 60min → 2h → 6h backoff; banner + Retry Now + status-bar countdown + tray notifications.
• 失败自愈默认开启 / Self-healing on by default：15 分钟，存量配置一次性迁移；-9 / -11 / -14 / -16 永久失败自动排除；右键「重试/移除全部失败」。Every 15 min with one-time migration; permanent errors excluded; "Retry/Remove all failed" context actions.
• 发布阻塞修复 / Release blockers：文件夹/ELC 展开、跳过计数、0 字节文件、验证取消标志、坏 ELC 按条隔离。Folder/ELC expansion, skip accounting, 0-byte files, verify-cancel flag, per-URL bad-ELC isolation.
• 可靠性 / Reliability：MD5 移出全局锁、配置不再每 5 秒重写、关机等验证落盘、看门狗竞态消除。MD5 off the global lock, no more 5-second config rewrites, shutdown waits for verify, watchdog race removed.
• 体验 / Experience：正则单例化（数百链接不卡）、转义链接可解、更新只走 https、XXE 封堵。Singleton regexes, escaped-link decryption, https-only updates, XXE blocked.
• 在线观看防连点 / Watch Online double-click guard：解析期间禁用按钮，杜绝并发双解析。Button disabled while resolving; no more concurrent double resolves.

详见 docs/CHANGELOG.md（含 4 语言：English / 繁體中文 / 日本語 / 한국어）。
See docs/CHANGELOG.md (available in 4 languages: English / 繁體中文 / 日本語 / 한국어).

📦 包内容 / Package

MegaDownloader.exe ＋ 12 个 DLL ＋ MegaDownloader.exe.config，须放同一目录。
MegaDownloader.exe + 12 DLLs + MegaDownloader.exe.config, keep in the same folder.

构建 / Build：.NET Framework 4.8 · x86 · Win7 SP1+
版本 / Version：Assembly 2.5.0.0 / InternalConfig 2.5
已知限制 / Known limitations：公开链接本质无端到端校验（仅长度）；配额倒计时为启发式估算；顶层系统菜单深色下仍浅色。Public links have no end-to-end checksum (length only); quota countdown is heuristic; top-level system menu stays light in dark mode.