Notable changes within the development of what will be the next version of Ubuntu 21.10 Impish Indri have already started to take shape and many of those that have been released are in regard to the graphical part of the system, since for example an important change as reported by my colleague Pablinux that the image of the system that is offered for testing is already using GNOME 40.
Now another major change has been released for Ubuntu 21.10 Impish Indri, Well, not long agoe approved the completion of the subject submissions, combining dark headers, light background, and light controls.
That is to say, what it will be has already been defined the delivery of the theme that is used in the distribution together with GNOME 40 and is that in the new version we will be presented with a completely clear version of the Yaru theme (the default theme), as well as the option to switch to a completely dark version (dark titles, dark backgrounds, and dark controls).
The decision to make this change instead of continuing to use the dark and light color scheme, it is explained by the lack in GTK3 and GTK4 of the ability to define different background colors and text for the title and the main window, which does not guarantee the correct functioning of all GTK applications when using combined themes (for example, in the gnome disk analyzer, a white input bar appears in the dark title).
Another important reason that is mentioned for making this decision is in relation to the large amount of work that is required to maintain non-standard themes, since they also detail that the problem is that GNOME does not provide an official programming interface and a set of guidelines for GTK themes, leading to broken compatibility with third-party themes in each new version of GNOME.
As discussed in # 2913 y # 2677, dark header bar in light theme is not compatible with Gtk3 and Gtk4 and we often cannot guarantee that errors will not be introduced into gtk applications. This removes the "yaru-light" theme and keeps "yaru" from now on as the completely light gtk theme. We need to make sure that the gnome control center settings page is updated correctly.
In addition, within the other expected changes in Ubuntu 21.10 Impish Indri is that a deviation from the use of the color aubergine was marked for the background of switches and widgets and whose color replacement has not yet been approved and is under discussion.
MoreoverAnother of the changes that we can see in Ubuntu 21.10 Impish Indri and that is not related to the graphical part, is that the developers They have started translating deb packages to use the zstd algorithm.
This change, which has been working on for several versions, means that in Ubuntu 21.10 Impish Indri almost package installation speed will be doubled, at the cost of a small increase in size (~ 6%).
And it is that the developers point out that in particular, support for using zstd was added to apt and dpkg in 2018 with the Ubuntu 18.04 version, but it was not used to compress packages. Whereas for example in Debian, zstd support is already included in APT, debootstrap and reprepro and is being reviewed before including it in dpkg.
When Julian Andres Klode and I added initial Zstandard compression support to Ubuntu's APT and dpkg on Ubuntu 18.04 LTS, we planned to get the changes accepted into Debian quickly and make Ubuntu 18.10 the first release where the new compression could speed up installations and upgrades of packages. Well, it took a little longer.
Finally if you are interested in knowing more about it About the changes that have been proposed for Ubuntu 21.10 Impish Indri, you can check the details in the following links.