Acrylic
In Zehn, the Transparency Effects option enables the Acrylic effect on various surfaces. Most of these surfaces are internally composited using backdrop blur. However, some surfaces can blur the content behind the window if you are willing to do a little additional setup!
You need to be using the Millennium patcher for this to work. omium First, install the DWMX plugin through Millennium's interface. This modifies Steam to use Windows' native compositor so we can have transparent windows.
Afterwards, make sure it is enabled. Steam will have to reload.
Now, as long as Transparency Effects is enabled in Zehn, you will have transparent window backgrounds on supported windows!
DWMX is supposed also enable background blur, but as of writing it does not seem to work. However, I do have a workaround to give your Steam that blur!
You will need the Windhawk modding marketplace to install a mod. I love this software and use many mods to customize the look of Windows 11, such as having square window corners and removing the forced grey border it puts atop certain processes.
First, you need to enable the steamwebhelper.exe process in Windhawk. This is in a default exclusion list because it has to do with games, so they took preventative measures to create a blacklist, and so this got thrown in there. You will have to head to Settings, expand Advanced Settings, and click on More Advanced Settings. Add it to the inclusion list, then save and restart.
Search for the Translucent Windows mod and install it.
Make sure the mod is enabled. Go to its Settings page and adjust the following...
Select Blur (AccentBlurBehind) in the dropdown. Set the color blend to 00000000 (transparent). The other effects do not seem to work with Steam, but we apply our own Acrylic noise and color in Zehn, so we just need the blur to composite behind the window.
If you are on Windows 11, scroll further down. Enabled the Border Color option, and set both color states to 0. This gets rid of the forced border that Windows 11 applies over certain applications. This may just be that these applications are not overriding this on their own, but we can make it happen.
Scroll up to the top and save!
Now, switch to the Advanced tab.
Add steamwebhelper.exe to the inclusion list. Enable Ignore Mod Inclusion/Exclusion Lists. If you find this seems to still affect other windows, you can add stuff such as dwm.exe and explorer.exe to the exclusion list. In my experience, this seems to be necessary if you have added them to the global inclusion list that you modified earlier.
And that should be all!
If you hate Windows 11 forced borders, you can make a fork of this mod to customize other processes. There are other mods that deal with borders as well.
Also, if you hate rounded corners on Windows 11, you can use the Disable rounded corners in Windows 11 mod. Add dwm.exe to its inclusion list.
