Starting with the release of Ubuntu 22.04 LTS, the firefox and firefox-locale deb packages will be replaced with stubs that install the Snap package with Firefox. The ability to install the classic deb package will be discontinued and users will be forced to either use the provided snap package or download builds directly from the Mozilla website. For users of the deb package, there is a transparent process for migrating to snap by publishing an update that will install the snap package and transfer the current settings from the user's home directory.
Recall that in the autumn release of Ubuntu 21.10, the Firefox browser was switched by default to be shipped as a snap package, but the ability to install a deb package was retained and remained available in the form of an option. Since 2019, the Chromium browser has also been shipped only in snap format. Mozilla employees are involved with the Firefox snap package.
The reasons for promoting the snap format for browsers are the desire to simplify maintenance and unify development for different versions of Ubuntu - the deb package requires separate maintenance for all supported branches of Ubuntu and, accordingly, assembly and testing taking into account different versions of system components, and the snap package can be formed immediately for all branches of Ubuntu. One of the important requirements for the delivery of browsers in distributions is the need for prompt delivery of updates to block vulnerabilities in a timely manner. Delivery in snap format will speed up the delivery of new versions of the browser to Ubuntu users. In addition, shipping the browser in snap format makes it possible to run Firefox in an additional isolated environment created using the AppArmor mechanism, which will strengthen the protection of the rest of the system from exploiting vulnerabilities in the browser.
The disadvantages of using snap are that it makes it difficult for the community to control package development and is tied to additional tooling and third-party infrastructure. The snapd process runs as root on the system, which poses additional threats if the infrastructure is compromised or vulnerabilities are discovered. The disadvantage is also the need to solve problems specific to snap distribution (some updates do not work, flaws pop up when using Wayland, there are problems with the guest session, there are difficulties with starting external handlers).
Another noteworthy change in Ubuntu 22.04 is the switch to using the GNOME session with Walyand by default on systems with proprietary NVIDIA drivers (if the drivers are 510.x or newer). On systems with AMD and Intel GPUs, the default transition to Wayland took place with the release of Ubuntu 21.04.
Source: opennet.ru