Current Limitation:
Currently, the Steam client only allows installing one instance of a game per computer. This makes it impossible to easily maintain separate versions, such as:

• A "Clean" version (vanilla, unmodified).
  
• A "Modded" version (using Steam Workshop and/or third-party mods from sites like Nexus Mods).
  
• A Stable version vs. a separate Beta/Branch version for testing.

Switching between these requires tedious manual management: uninstalling/reinstalling, moving game folders, or using complex symlinks/workarounds. This is time-consuming and risks breaking installations or save files.

Proposed Solution:
Add an "Install Additional Copy" (or "Duplicate Installation") option within the Steam client for games.

Mechanism:

• Right-click on a game in the Library -> Manage -> "Install Additional Copy".
  
• The user chooses an installation location (e.g., Steam\steamapps\common\GameName_Clean, Steam\steamapps\common\GameName_Modded).
  
• Steam creates a new, fully independent game instance in the chosen folder.
  
• Crucially: This copy should intelligently share immutable assets (like core game files, HD textures from DLCs) already present in the first installation to minimize disk space duplication. Only truly unique files needed for independence (configs, modded files, potentially executable if modified) should be duplicated.

Key Features:

• Independent Modding: Each copy can have its own completely separate set of mods (Steam Workshop subscriptions, manual mods). Enabling/disabling mods in one copy does not affect the others.
  
• Separate Beta Branches: Install one copy on the default/public branch and another on a specific beta branch (e.g., public-test or experimental) simultaneously.
  
• Independent Settings & Saves: Each copy maintains its own configuration files (.ini, etc.) and save game location (unless the game uses cloud saves exclusively - this would need per-instance handling).
  
• Clear Identification: Each instance in the Steam Library should have a unique, user-assignable name or suffix (e.g., "Cyberpunk 2077 [Clean]", "Cyberpunk 2077 [Modded]", "RimWorld [Beta 1.4]") for easy differentiation.

Benefits:

Why Steam Should Implement This:
This feature directly enhances Steam's value for its most engaged users (modders, testers, enthusiasts). It addresses a common, long-standing workflow limitation in a user-friendly way, leveraging Steam's existing installation management. The smart asset reuse makes it a practical solution, not just a convenience.

Key improvements in the translation/adaptation:

• Clear & Catchy Title: Immediately states the core feature ("Install Multiple Copies") and primary use cases ("Modding/Beta Testing").
  
• Structured Problem Definition: Clearly lists the specific limitations users face.
  
• Detailed Solution Mechanism: Explains how the "Install Additional Copy" should work, emphasizing smart asset sharing to address the disk space concern.
  
• Explicit Key Features: Bullet points highlight the crucial independence aspects (mods, branches, settings/saves, naming).
  
• Comprehensive Benefit Table: Groups benefits logically (Modders, Testers, All Users, Technical, Usability) for maximum impact. This format is very effective on the forum.
  
• Strong Closing Argument: Summarizes why Valve should prioritize this (engages core users, solves a common pain point, technically feasible).
  
• Professional Terminology: Uses terms like "vanilla", "instances", "beta branches", "asset sharing", "workflow limitation".
  
• Conciseness: Avoids fluff while being thorough.