ChromeOS 104 is released starting today with many major interface updates that improve the way the operating system is used.
ChromeOS 104 introduces dark and light themes that touch every aspect of the user interface. This includes the shelf, the app launcher, the Files app, and the backgrounds of various pages in the settings. You can enable the dark theme from the second page of Quick Settings. Google has also created wallpapers that “subtly shift from light to dark,” depending on the theme you set.
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After the ChromeOS 104 update, you’ll notice that the month and day now appear to the left of the time on the shelf. Clicking opens a monthly calendar with the ability to tap a day to see all events, with an additional click opening the Google Calendar PWA. You can view other months and quickly return to “Today.”

This takes up the same size as Quick Settings, with all available notifications displayed directly above. Notifications from the same sender are now grouped together, and there are larger touch targets for notification actions.
The redesigned Launcher in ChromeOS 104 is more compact and doesn't take up your entire screen. Additionally, some may be able to quickly search for Android from the Play Store with built-in ratings.
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ChromeOS version 104 introduces a more comprehensive Gallery app (with a new purple icon) that can open PDF files with the ability to fill out forms, sign documents, and create text annotations, such as highlights.
ChromeOS 104 also features a new Wallpaper & style app , which you can access by right-clicking on the shelf and selecting the latter option. In addition to the Google-curated collections, you can set wallpapers from your Google Photos library . There's also the option to select an album and have a new wallpaper appear daily.

This experience also allows you to set the device theme (auto-switching available) and Screen Saver with three available styles: Slide show, Feel the breeze and Float on by.
Source: 9to5google.com
