Canonical has been making little less than controversial decisions for a long time. The Snap Store is one of them, a store that favors snap packages and doesn't even support flatpaks. The last movement that has not left anyone indifferent has been to offer firefox only as snap en Ubuntu 22.04. We may like them more or less, but the most striking problem is how long it takes for applications to open cold.
I have come to see how Firefox takes half a minute to open for the first time, this on a low-resource computer. The browser is one of the most used applications on any computer, and Canonical knows it, so it has been trying for a long time to speed up the startup of Firefox, and it seems that it has succeeded: at the moment, the first startup of Firefox has been reduced by 50%.
Ubuntu 22.04 only offers Firefox as a snap
Much of the credit goes to Mozilla, who have introduced a change in which only copy one language at a time on startup instead of trying to copy all the languages. The copied language depends on what we have configured in the system. And that is the problem with snap packages: they start late because they re-configure some parameters, but the second time they open faster.
Also, the GNOME and GTK themes have been changed to LZO and XZ. Canonical has already done this for the Firefox snap, although at the moment it is still based on the GNOME and GTK theme. This can make the design less consistent, but it can be worth it.
All information about this improvement is available at this link from the Canonical blog. It is article number 3 on the matter, which makes it clear that they are working seriously to prevent Firefox as a snap from taking so long to open.
The truth is quite noticeable the change