You can now open Settings > Personalization > Desktop Background, and choose any .webp image as the background. This feature is included in Build 26220.7653 for testers, and it’ll be coming to Windows 11 24H2 or 25H2 machines in the future. It’s not a big deal, but I still find it a nice addition.

.webp, which is typically much smaller than JPG and especially PNG at similar quality, has always been supported on Windows. Windows apps or web browsers can load .webp, but if you pick a background in Settings > Personalization > Background, Windows doesn’t just “show an image.”

Adding WebP here means Windows is now reliably decoding WebP in that wallpaper path, instead of forcing you to convert to PNG/JPG first.

Microsoft has been mulling video formats for your desktop background, but recent builds have no sign of the feature

Microsoft has been internally testing .mp4 or other video formats for Windows 11’s desktop background.

If you set up a video as your wallpaper, it will play automatically in a loop, but it won’t drain your battery as much as third-party apps. For those unaware, there are third-party apps like Lively wallpaper that allow you to achieve the same result as the video below:

Another similar one is WallpaperEngine, which is very popular on Stream, and it simply lets you set a video as a wallpaper. All of these integrations are quite complicated, but Microsoft’s idea seems to be very straightforward, and it will be integrated into Settings > Personalization > Background.

In the above screen, you need Browser photos (yes, it’s not yet renamed), and then you need to choose the video-related file formats, such as .webm, mp4, .m4v, .mov, .wmv, .avi, .mkv, and .webm.

I selected an MP4 file and restarted Explorer.exe, and the video was automatically applied to the desktop.

As you can see in the above demo, Windows plays the short Windows Bloom wallpaper as my desktop background, and it’s in a loop. The Bloom video is not the right video for the background, but if you have something aesthetic with minimal movements, you might really enjoy the video backgrounds.

In our tests, Windows Latest observed that there’s no size limit, so any video could be applied, and we did not notice an increase in resources or power usage, but the catch is that Windows 11’s video wallpaper feature first appeared in preview builds in September, and it’s missing from the recent builds.

Is the Video wallpaper idea canned now? We don’t know, and only time will tell. For now, we’re only getting .webp as a desktop background.

The post Microsoft lets you use .webp images as Windows 11 desktop background, no signs of Video wallpaper yet appeared first on Windows Latest

Welcome to F# Weekly,

A roundup of F# content from this past week:

News

• Which programming languages are most token-efficient? – Martin Alderson
• How to Build Android Widgets with .NET MAUI – .NET Blog
• How We Synchronize .NET’s Virtual Monorepo – .NET Blog
• .NET and .NET Framework January 2026 servicing releases updates – .NET Blog
• Copilot Studio Extension for Visual Studio Code Is Now Generally Available – Microsoft 365 Developer Blog
• Copilot Memories – Visual Studio Blog
• Announcing Agent Academy: Operative | Power Platform Developer Blog
• Aspire for JavaScript developers | Aspire Blog
• December 2025 (VS Code version 1.108)

#fsharp mentioned finally in a #dotnet @fireship.bsky.social video youtu.be/MFsYaRnrcPQ?… yessss

— jkone27 (@jkone27.bsky.social) 2026-01-16T17:44:57.783Z

Videos

• .NET in 100 Seconds
• Blazor Community Standup – Planning the future of Blazor in .NET 11
• .NET AI Community Standup Topic: Let’s talk about the new .NET AI Stack
• On .NET Live | Orleans Deep Dive: Routing, Placement & Balancing

Blogs

• Inferring Memory Lifetimes | SpeakEZ Technologies
• Arity On The Side of Caution | SpeakEZ Technologies
• Dimensional Type Safety Across Execution Models | SpeakEZ Technologies
• Gaining Closure | SpeakEZ Technologies

We're introducing a new approach to memory management in Fidelity: the compiler tracks data flow, determines where values escape their scope, and infers lifetimes automatically. Explicit arenas when you need them, inference when you don't. #fsharp speakez.tech/blog/inferri…

— SpeakEZ.tech (@speakeztech.bsky.social) 2026-01-14T22:24:11.157Z

Highlighted projects

• nietras/Sep: World’s Fastest .NET CSV Parser. Modern, minimal, fast, zero allocation, reading and writing of separated values (`csv`, `tsv` etc.). Cross-platform, trimmable and AOT/NativeAOT compatible.
• lamg/migrate: Declarative migrations for SQLite databases
• tonyx/Sharpino: A little F# event-sourcing library.
• JordanMarr/FSharp.DurableExtensions: Extensions for Azure Durable Functions for strongly typed activity calls.
• rdipardo/Fornax.Seo: A SEO meta tag generator for Fornax
• JordanMarr/Agent.NET: A composable AI agent framework for .NET.
• fs-fio/FSharp.FIO: A Type-Safe, Purely Functional Effect System for Asynchronous and Concurrent F#
• fsprojects/TickSpec: Lean .NET BDD framework with powerful F# integration

New Releases

• FSharpPlus 1.9.1
• Oxpecker.OpenApi 2.1.1
• XParsec 0.3.1
• FSharp.DurableExtensions 2.0.1
• Hedgehog 2.0.3
• Hedgehog.NUnit 1.0.0
• CCFSharpUtils 0.1.8
• Sharpino.Templates 1.2.0
• Fornax.Seo 1.5.0
• FSharp.Compiler.Service 43.10.102
• FSharp.Core 10.0.102
• FsLambda.Templates 1.0.14
• FSharp.ReactiveWpf 0.0.9
• FAkka.WebSocket 1.557.10.101002
• TickSpec.Unofficial 0.5.0
• Hedgehog.Stateful 1.0.0-beta1
• ARCtrl 3.0.0-beta.16
• AgentNet 1.0.0-alpha.2.1
• FSharp.FIO 0.0.38-alpha

The data above is from this article martinalderson.com/posts/which-…

— Bozhidar Batsov (a.k.a. Bug) (@batsov.net) 2026-01-16T09:32:55.394Z

That’s all for now. Have a great week.

If you want to help keep F# Weekly going, click here to jazz me with Coffee!

The U.S. Supreme Court will hear Monsanto's argument that federal pesticide law should shield it and parent company Bayer from tens of thousands of state lawsuits over Roundup since the Environmental Protection Agency has not required a cancer warning label. The case could determine whether federal rules preempt state failure-to-warn claims without deciding whether glyphosate causes cancer. The Los Angeles Times reports: Some studies have found it is a likely carcinogen, and others concluded it does not pose a true cancer risk for humans. However, the court may free Monsanto and Bayer, its parent company, from legal claims from more than 100,000 plaintiffs who sued over their cancer diagnosis. The legal dispute involves whether the federal regulatory laws shield the company from being sued under state law for failing to warn consumers. [...] "EPA has repeatedly determined that glyphosate, the world's most widely used herbicide, does not cause cancer. EPA has consistently reached that conclusion after studying the extensive body of science on glyphosate for over five decades," the company told the court in its appeal. They said the EPA not only refused to add a cancer warning label to products with Roundup, but said it would be "misbranded" with such a warning. Nonetheless, the "premise of this lawsuit, and the thousands like it, is that Missouri law requires Monsanto to include the precise warning that EPA rejects," they said. On Friday, the court said in a brief order that it would decide "whether the Federal Insecticide, Fungicide, and Rodenticide Act preempts a label-based failure-to-warn claim where EPA has not required the warning." The court is likely to hear arguments in the case of Monsanto vs. Durnell in April and issue a ruling by late June.

Read more of this story at Slashdot.

A federal judge has temporarily lifted the Trump administration's suspension of the Coastal Virginia Offshore Wind, allowing construction on the largest offshore wind project in the U.S. to resume. CNBC reports: Judge Jamar Walker of the U.S. District Court for the Eastern District of Virginia granted Dominion's request for a preliminary injunction Friday. Dominion called the Trump suspension "arbitrary and illegal" in its lawsuit. "Our team will now focus on safely restarting work to ensure CVOW begins delivery of critical energy in just weeks," a Dominion spokesperson told CNBC in a statement Friday. "While our legal challenge proceeds, we will continue seeking a durable resolution of this matter through cooperation with the federal government," the spokesperson said. Dominion said in December that "stopping CVOW for any length of time will threaten grid reliability for some of the nation's most important war fighting, AI and civilian assets." Coastal Virginia Offshore Wind is a 176-turbine project that would provide enough power for more than 600,000 homes, according to Dominion. It is scheduled to start dispatching power by the end of the first quarter of 2026. In December, the Trump administration paused the leases on all five offshore wind sites currently under construction in the U.S., blaming the decisions on a classified report from the Department of Defense.

Read more of this story at Slashdot.

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