OpenGlass: putting the Aero Glass frame back on Windows 10 and 11

A theme tool that replaces part of the window manager

OpenGlass restores the full glass effect to window frames on Windows 10 and later, with control over blur, reflections, colorization, caption rendering and theme integration. The project description puts it as Aero Glass for Windows 10 and later, and the topic list gives away the method: d3d11, direct2d, dwm, shader, reverse-engineering, disassembly and undocumented.

The mechanism is the reason the tool works. The Aero Glass look shipped with Windows Vista and Windows 7, and it was removed in Windows 8, so the effect has to be reintroduced into a component that was not written to support it. OpenGlass does that by substituting its own implementation of parts of the Desktop Window Manager, the compositor that draws every window frame on the system.

That is a fundamentally different undertaking from shipping a theme file. The compositor is closed, undocumented and has no supported extension point, and the project says so plainly in its support section: DWM offers no official extension mechanism, so future Windows updates may break OpenGlass, and ongoing support cannot be guaranteed. The project is developed in spare time and released under the GPLv3.

The audience is stated in the README as advanced users who are comfortable troubleshooting DWM, and the project points at DWMBlurGlass as a simpler alternative. The project itself is written in C++ and its layout shows a C++ solution: `OpenGlass.slnx` at the root, with `Common/`, `OpenGlass/`, `OpenGlassGUI/`, `OpenGlassHost/`, `OpenGlassRenderTest/`, `OpenGlassTests/` and `OpenGlassThemeExtension/` directories, plus `ports/` and `Scripts/`.

The support table is narrow on purpose

The supported Windows versions are given as a table, and the boundaries are as important as the entries.

| Windows version (OS build) | Status | | --- | --- | | Windows 10 1809-22H2 (17763-19045) | Stable | | Windows 11 21H2-25H2 (22000-26200) | Stable | | Windows 11 26H2 (26300) | Stable | | Windows 11 26H1 (28000) | Experimental | | Windows Server 2022 (20348) | Supported |

The rule underneath is stricter than the table. Only the General Availability releases listed are supported, and Insider builds and other unlisted versions are unsupported. Windows 11 26H1 is listed but marked experimental, so it works at the time of writing and is not covered by the same assurance as the stable entries.

Two features of the table are worth noting. Windows Server 2022 appears at all, which is unusual for a consumer visual effect, and it suggests the tool is used in environments where a consistent desktop appearance across a fleet matters. And the granularity is by OS build number, not by marketing name, which is what you would expect from a project that patches internals: a build number is what determines whether the substitution still lines up with the system's expectations.

The README points to a wiki page on compatibility and DWM architectures for the details, which is where the reasoning behind the table lives. Since the table is the first thing to check and it is likely to change, the build number of the machine you are about to install this on is the first thing to look up.

Installer, GUI and a Sync button that never saves for you

The quick start is four steps, and one of them involves administrator rights.

You download `OpenGlassSetup.exe` from the releases, run the installer, and the installer selects the matching DWM implementation for your system before the GUI opens. The tool requests administrator rights, which follows from the fact that it replaces a system component.

Inside the GUI, the behaviour is more careful than a typical shader tool. Settings are written immediately, but Save accepts the changes, while Revert or closing the GUI undoes pending changes. That distinction between a live preview and a committed state is what makes it safe to experiment with a change that could leave your desktop unreadable.

There is a separate path for changes made outside the GUI. Holding Shift while opening More and choosing Sync reloads the settings, the preset library and the diagnostics. Two properties are called out explicitly: Sync never saves or reverts implicitly, and you should Save or Revert any pending changes first. So the three ways to act are distinct. Save commits, Revert undoes, Sync pulls in outside changes without touching your pending state.

The most important line in the README is the emergency exit. Holding Ctrl+Win+Shift+Q terminates DWM if the system becomes unresponsive. Since DWM is the compositor, a broken or wedged DWM means a broken desktop, and that key combination is the documented way back. It is a blunt instrument, killing the process rather than fixing it, but it is the safety net the project offers.

Building the solution with msbuild and a vcpkg manifest

The build command is a single msbuild invocation, and it uses the newer solution extension:

msbuild OpenGlass.slnx /m /restore /p:Configuration=Release /p:Platform=x64

`/m` enables parallel projects, `/restore` pulls in the NuGet and vcpkg dependencies, and the configuration and platform are passed as properties. The x64 platform is the one that matters here, since the project patches a 64-bit system component.

The repository carries `vcpkg.json` and `vcpkg-configuration.json` at the root, so the C++ dependencies are declared as a manifest rather than installed by hand. The `ports/` directory sits alongside them, which usually means local port overrides for dependencies that are not in upstream vcpkg yet, a common need for a project that works against undocumented Windows internals.

There is also a `OpenGlassRenderTest/` project, which is a rendering harness rather than part of the shipped tool, and `OpenGlassTests/`. The wiki has a page on building OpenGlass covering prerequisites, tests and packaging.

One caveat on the artefacts. The README states that CI artifacts are unsigned validation builds, not releases, and that the developer theme extension DLL and PDB are uploaded separately. So a green CI run does not give you an installable package, and the theme extension is not part of the normal release pipeline at all.

The theme extension is for developers and is not installed for you

OpenGlass has a Windows theme integration component, and the README is careful to say who it is for and who has to do the work.

The theme extension connects Windows theme application and the classic color panel to OpenGlass, and it is intended for developers who build and customize it from source. The installer does not include or manage it.

That sentence rules out a common expectation. Installing OpenGlass from the setup executable gives you the glass effect and its settings, but the piece that makes the system colour picker and the theme mechanism drive OpenGlass is a separate build-and-install task documented in a wiki page on Windows theme integration.

The repository layout matches that description. `OpenGlassThemeExtension/` is a separate top level directory alongside `OpenGlassGUI/`, and the CI note says the theme extension DLL and PDB are uploaded separately from the main artefacts, which is consistent with it being a developer component rather than a shipped one.

The configuration side is documented in two wiki pages, a configuration and registry reference for editing scopes, colour options, presets and recovery behaviour, and a preset library guide for preset packages. Recovery behaviour being a documented topic says something about the risk profile of the tool, and it is where you would look if you need to undo what a preset did.

Against a translucent taskbar tool and against leaving DWM alone

The realistic comparison is not with another Aero clone but with the two things you could do instead of installing this.

The first is a tool that only changes the taskbar. TranslucentTB is named in the credits as the project whose C++ structure inspired OpenGlass, and it does the one part of the Aero look that most people notice, translucency, by talking to the shell rather than replacing the compositor. The difference in approach is scope and risk: a taskbar change is a small surface with a well understood recovery story, while OpenGlass replaces part of the system compositor, which is why it needs administrator rights, why it has an emergency exit shortcut, and why it needs a compatibility table tied to OS build numbers. DWMBlurGlass is offered by the project itself as the simpler alternative.

The second alternative is to leave the system alone. Windows 11 has its own transparency and mica-like surfaces, and if the Aero look is a preference rather than a requirement, a theme that the system supports natively carries none of the upgrade risk. The cost of that choice is that you do not get the specific blur and reflection behaviour Aero had, and you would be tuning settings in a panel Microsoft designed to be different.

A third option is the remote desktop angle, where a machine with the Aero look is only ever used through a session and the local desktop is never seen. That removes the risk from the machine you work on, though not from the machine hosting the session.

What OpenGlass offers that none of these do is the full effect with per-element control, blur, reflections, colorization and caption rendering, on a modern Windows build, with a preset library for sharing configurations. The price is that it depends on undocumented internals that the vendor can change without notice, and the project is candid that this makes future support a matter of luck rather than schedule.

Editorial conclusion

Adopt OpenGlass if you want the Aero Glass frame on a Windows 10 or 11 machine and you are prepared to troubleshoot the Desktop Window Manager when a Windows update changes its internals. Do not adopt it on a machine you cannot afford to repair, since it replaces a core system component and the emergency exit key combination is the only recovery path the project documents, and check first that your exact OS build appears in the support table, because unlisted versions and Insider builds are explicitly unsupported.

Frequently asked questions

Official sources

1. ALTaleX531/OpenGlass on GitHub
2. Issues
3. License: GPL-3.0
4. README
5. Releases