---
title: "GameDVR_FSEBehavior and GameDVR_FSEBehaviorMode: clearing the global fullscreen optimization overrides"
description: "GameDVR_FSEBehavior and GameDVR_FSEBehaviorMode under GameConfigStore are global switches that force fullscreen optimizations on or off for every game."
url: https://frozentweaks.com/tweaks/clear-fullscreen-optimization-overrides
author: Frost LIVE, Founder of Frozen Tweaks
published: 2026-10-08
updated: 2026-10-08
category: "Windows"
source: Frozen Tweaks (https://frozentweaks.com)
---

# GameDVR_FSEBehavior and GameDVR_FSEBehaviorMode: clearing the global fullscreen optimization overrides

**Short answer:** GameDVR_FSEBehavior and GameDVR_FSEBehaviorMode under GameConfigStore are global switches that force fullscreen optimizations on or off for every game. Tweak packs often set them and leave them behind. This tweak deletes both values, so Windows and each game decide again.

## In the app

- Switch: Purge FSE Shims (Windows, Pro, Advanced)
- Undo: One-way. Purged compatibility flags aren't put back.
- Game profiles that switch it on: Counter-Strike 2, Deadlock, Dota 2 and 9 more
- Catalog row: https://frozentweaks.com/tweaks#t-1058

## What it does

GameDVR_FSEBehavior and GameDVR_FSEBehaviorMode under GameConfigStore are global switches that force fullscreen optimizations on or off for every game. Tweak packs often set them and leave them behind. This tweak deletes both values, so Windows and each game decide again.

In the app the switch is called "Purge FSE Shims", described there as: Removes the stored fullscreen optimization overrides, so games go back to their own fullscreen mode.

## When it helps

- Cleaning up after old tweak packs when fullscreen behaves oddly: alt-tab problems, wrong refresh rate, capture not working.

## When it hurts

- It is one-way: if you wanted fullscreen optimizations forced off, you set that again afterwards.
- It removes what the Game DVR tweak in this app sets for fullscreen behavior, so use one or the other.

## What it writes

Read from the app's source. "Switching it off" is what the app writes when you turn the tweak off again.

- Deletes the value `GameDVR_FSEBehavior` under `HKCU\System\GameConfigStore`.
- Deletes the value `GameDVR_FSEBehaviorMode` under `HKCU\System\GameConfigStore`.

## How to undo it

This tweak is one-way in the app: switching it off does not put things back. Purged compatibility flags aren't put back.

## Verdict

A cleanup step for a PC with a tweaking history. On a clean install there is nothing to delete.

## Questions

### Is "Purge FSE Shims" safe to switch on?

A cleanup step for a PC with a tweaking history. On a clean install there is nothing to delete. The main cost: It is one-way: if you wanted fullscreen optimizations forced off, you set that again afterwards.

### How do I undo it?

In the app this one is one-way. Purged compatibility flags aren't put back.

### Is "Purge FSE Shims" free in Frozen Tweaks?

It is part of Frozen Pro and Elite. You can also make the change by hand with the values on this page.

## Related guides

- [Windows 11 Gaming Optimization: What Still Works in 2026](https://frozentweaks.com/guides/windows-11-gaming-optimization)
- [How to Increase FPS on PC: The Complete 2026 Guide](https://frozentweaks.com/guides/how-to-increase-fps-on-pc)

## More tweak explainers

- [Language feature auto-install](https://frozentweaks.com/tweaks/disable-language-feature-auto-install)
- [File Explorer thumbnails](https://frozentweaks.com/tweaks/disable-explorer-thumbnails)
- [Windows Update Medic Service](https://frozentweaks.com/tweaks/disable-windows-update-medic-service)

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Written by Frost LIVE, founder of Frozen Tweaks. Canonical version: https://frozentweaks.com/tweaks/clear-fullscreen-optimization-overrides