Moziilla announced asFirefoxWindows users get a new experimental feature in version 142: Progressive Web Apps (PWA).This feature has been present in the desktop version of Chrome since Chrome 70 version in 2018.
The development history of PWA in Firefox is quite bumpy. As early as the Firefox 73 (Nightly) period, Mozilla tried an experimental implementation of PWA called "Site-Specific Browsers (SSB)", but this feature was never fully developed and was removed by Mozilla in January 2021.
At the time, Mozilla explained that the feature had "multiple known issues" and that keeping it in would take the Firefox team's time away from troubleshooting.
In March of this year, Mozilla released Firefox Nightly version 141, which added this feature and named it "Taskbar Tabs".
Firefox product manager David Rubino explained that this new implementation is different in design. Web applications will retain Firefox's main toolbars, including the address bar, extensions and bookmarks, to ensure that users still feel like they are in the browser.