Valve has pushed a new Steam client beta that quietly changes a long-standing behaviour: Windows games added to Steam from outside the store now launch through Proton by default, rather than falling back to attempts at native execution or requiring users to configure a compatibility tool themselves. According to Phoronix, which reported on the beta's release, the update targets the friction Linux gamers have long faced when importing non-Steam titles — a small quality-of-life change that removes a recurring manual step.
簡而言之： Steam client beta 起，由外部匯入的 Windows 遊戲會自動以 Proton 執行，毋須再手動設定相容性工具；該功能目前仍屬 beta 測試階段。
For years, users importing a Windows-only executable had to know to right-click the title, open Properties, and manually assign Proton or ProtonGE. With the beta, that selection is made automatically. The change builds on Proton — Valve's Wine-and-DXVK-based compatibility layer — which has effectively been the default for Linux Steam Play titles since 2022. What's new here is that the default now extends to non-Steam imports as well.
The beta also includes DXVK improvements and other Linux-facing refinements, per Phoronix's coverage. Users testing it can opt out: in Steam settings, navigate to the account tab's beta participation dropdown, select "None", and restart the client to return to the stable branch. The beta is opt-in, and Valve has not announced a timeline for when it will reach stable clients.
The anti-cheat caveat hasn't changed
The default flip does not fix the story's biggest known problem. Games using kernel-level or server-side anti-cheat systems — from titles like PUBG and Fortnite to a long tail of others — remain broken or unplayable on Linux, with or without Proton. Proton's translation layer can render the graphics path (via DXVK or VKD3D) and the sound, but anti-cheat kernels typically do not tolerate the translated environment. Some publishers have since shipped Linux-native builds of their anti-cheat clients, but this beta does nothing to change that landscape. Users should still expect specific competitive and live-service titles to be unlaunchable, and the default merely removes a manual step — not a compatibility barrier.
Per-game override: the escape hatch
Linux gamers should also know that the new default is not a one-way door. Any title imported into the Steam library can be manually reconfigured after the fact: right-click the game in the library list, select Properties, go to Compatibility, and tick the "Force the use of a specific Steam Play compatibility tool" box. From there, the user can choose between Proton versions, Proton Experimental, and community builds such as Proton-GE — or deliberately disable Proton entirely for titles that genuinely run better with native execution or a different runtime. Anyone who encounters a broken import after the beta ships will find that override in the same place it has always lived.
Why it matters
The change is modest but telling: Valve is treating Proton as part of the substrate of the Steam client on Linux, not as an opt-in experiment. For the open-source community, it's a vote of confidence in Proton, DXVK, and the wider graphics translation stack. For IT professionals and hobbyists running mixed environments, the takeaway is simpler: the beta removes a step, not a limitation — anti-cheat titles still stand as the unmoved caveat, and anyone who wants the old behaviour can opt out with two clicks in the beta settings.
Valve 已推出新的 Steam client beta，當中悄然改變了一項長久以來的行為：由商店外部匯入 Steam 的 Windows 遊戲，現在預設以 Proton 啟動，而不再回退至嘗試原生執行，亦毋須使用者自行設定相容性工具。據率先報道 beta 版本推出的 Phoronix 指出，是次更新針對的正是 Linux 玩家在匯入非 Steam 遊戲時一直面對的阻力——一個小小的體驗改善，移除了一個反覆出現的手動步驟。
簡而言之： 自 Steam client beta 起，由外部匯入的 Windows 遊戲會自動以 Proton 執行，毋須再手動設定相容性工具；該功能目前仍屬 beta 測試階段。
多年來，匯入 Windows 專用執行檔的使用者，必須知道要右擊該遊戲、開啟「內容」，再手動指定 Proton 或 ProtonGE。有了 beta 版本，這項選擇會自動完成。是次改動建立於 Proton 之上——Proton 是 Valve 基於 Wine 及 DXVK 所建立的相容性層，自 2022 年起實際上一直是 Linux Steam Play 遊戲的預設選項。今次的新意在於，這項預設已延伸至非 Steam 匯入的遊戲。
根據 Phoronix 的報道，beta 版本亦包含 DXVK 的改進，以及其他針對 Linux 的優化。測試該版本的使用者可以選擇退出：在 Steam 設定中，進入「帳戶」分頁的 beta 參與下拉選單，選擇「無」，並重新啟動 client 即可返回穩定版本分支。此 beta 採用自願加入模式，而 Valve 尚未公布何時會推送至穩定版本 client。
反作弊的限制依然存在
預設值的翻轉並未解決此報導中最大的已知問題。採用 kernel-level 或 server-side 反作弊系統的遊戲——從 PUBG、Fortnite 等熱門作品以至大量長尾遊戲——在 Linux 上仍然無法正常運行或根本無法執行，無論有沒有 Proton 均是如此。Proton 的轉譯層（透過 DXVK 或 VKD3D）可以處理圖形路徑及聲音輸出，但反作弊核心通常無法容忍被轉譯後的執行環境。其後雖有部分發行商推出了其反作弊客戶端的 Linux 原生版本，但本次 beta 對此格局並無任何改變。使用者仍須預期部分競技類及 live-service 遊戲無法啟動——預設值僅僅移除了一個手動步驟，而非解決了相容性障礙。
逐個遊戲覆蓋設定：逃生門
Linux 玩家亦應知道，新的預設值並非不可逆轉。任何匯入 Steam library 的遊戲，事後仍可手動重新設定：在 library 清單中右擊遊戲，選擇「內容」，進入「相容性」，然後勾選「強制使用特定 Steam Play 相容性工具」。使用者可於此在不同 Proton 版本、Proton Experimental 以及社群版本（例如 Proton-GE）之間作出選擇，亦可為原生執行或另一個 runtime 表現更佳的遊戲，刻意完全停用 Proton。任何在 beta 推出後發現匯入遊戲出現故障的使用者，都會發現這個覆蓋設定一直存在於原位。
為何重要
是次改動雖然有限，但意義深遠：Valve 正將 Proton 視為 Linux 版 Steam client 基層架構的一部分，而不再是一個自願參與的實驗。對開源社群而言，這是對 Proton、DXVK 以及整個圖形轉譯技術堆疊的投信任票。對運行混合環境的 IT 專業人士和愛好者而言，重點更為簡單：beta 移除的是一個步驟，而非一項限制——反作弊遊戲仍然是不變的限制條件，而任何希望維持舊有行為的人，都可以在 beta 設定中以兩下點擊退出。