OptiScaler, a compatibility layer for upscaling and frame generation technologies such as FSR4, DLSS, and XeSS, has been released in version v0.9.3.

This release focuses on fixing issues introduced in the 0.9 series: ResizeBuffers1 crashes are resolved, an RTX Remix incompatibility is fixed, and the OptiScaler Overlay is visible again in games like Metro EE and the STALKER Trilogy remasters thanks to the new Manual Input Polling option. FSR4 is now auto-enabled on RDNA4 graphics cards by default.

New and improved MAJOR features in 0.9.3:

• Fixed ResizeBuffers1 error, improvements to swapchain backbuffers
  • No more crashes on boot on certain games
• Fixed and improved HDR tonemapping for Overlay theme presets customisation
• Fixed FSR4 driver update not working
• Added Swapchain Waitable Object Simulation
  • Fixed XeSS3 + Unity games getting stuck when loading
• Added null check before copying InFeatureInfo
  • Fixed RTX Remix crash
• Added Manual Input Polling option
  • Crude, but effective fix for invisible Opti Overlay in games such as Metro EE, STALKER Trilogy remasters, DL2, DLTB
• Improved and re-enabled precompiled shaders
  • Should fix Lego Batman scene change stutters
• 007 First Light fixes and improvements
• OptiScaler now tries enabling FSR4 on RDNA4 by default
• Added auto FGResourceFlip enabling for OptiFG when Unity is detected
• Added late loading option for ASI files (LateAsiPluginsDelay option in OptiScaler.ini)
• Fix for DLSSD feature reverting to DLSS

Regarding FSR4 VK w/Dx12 on Linux:

• Proton 11 adds the missing required Wine extensions, VK w/Dx12 should be working now, but needs more testing
• RADV may have a massive performance drop compared to AMDVLK (unrelated to OptiScaler)
• FSR4-FG requires Mesa 25.2+ and Wine prefix set to Win 11

Source: GitHub