What is the detail that does an release be LTS?

I see focal 20.04 is LTS and hirsute 21.04 end support in 01-2022.
What main detail does focal be LTS and even hirsute being recent not is LTS ?

Only LTS are more secure ?
What is the release with better performance stability ? focal or hirsute ?
In release date has details about LXQT version. Focal 20.04.0 LXQT 0.14.1 and hirsute 21.04 LXQT 0.16.
Focal 20.04.3 use what LXQT version ?
Focal 20.04.3 use what Linux kernel version ? 5.11 ? If yes is the same version in hirsute ?

In moment I not see an solution to problem with white color being much high value having (bright or gamma) in hirsute and testing focal 20.04 has that problem , but extremely less than hirsute.

Thanks for your reply.

Ubuntu offers two primary paths for the standard year.month products (ie. deb based systems).

Ubuntu LTS which are the first release on an even year, ie. 6.06, 8.04, 10.04, 12.04, 14.04, 16.04, 18.04, 20.04… Excluding the first LTS (which was a 2006-June release thus 6.06), all releases have been in April thus are shown as a .04 using the Ubuntu year.month format.

Ubuntu have releases every 6 months, so in between those releases are numerous (3 between each LTS) non-LTS releases, eg. between 20.04 and 22.04 there will be

  • 20.10 or the 2020-October release
  • 21.04 or the 2021-April release (an odd year so no LTS)
  • 21.10 or the 2021-October release that has just hit UI (user-interface freeze)

All are treated as stable and secure, the primary difference is the length of time where security patches are provided for them (LTS releases are secure for longer)

For details about each release, the best place to go is the actual release notes, ie.

  • Lubuntu 20.04 LTS can be found here and general Ubuntu release announcement found here

  • Lubuntu 21.04 can be found here or a general Ubuntu release annoucement found here

Note: I could have given other links for the Ubuntu release announcements, but my browser knows those links as I’m the person who posted them, and I know they contain full details and links.

Ubuntu LTS releases have two kernel stack choices

  • GA or the kernel stack that the system is released with, or
  • HWE or the hardware enablement stack; which upgrades for the first two years of it’s life, before settling on the GA stack of the next LTS.

Ubuntu 20.04 LTS was released with the 5.4 kernel, thus it’s the GA stack. Lubuntu 20.04 LTS media installed and defaulted to the GA stack, as did Lubuntu 20.04.1 LTS media.

At 20.04.2, if using the HWE stack, your system kernel upgraded to the 5.8 kernel, which was the kernel stack from 20.10 (which released months before 20.04.2). Lubuntu 20.04.2 & later media defaults to the HWE stack.

At 20.04.3, if using the HWE stack, your system kernel upgraded to the 5.11 kernel, which was the kernel stack from 21.04 (again 21.04 released months before 20.04.3)

At 20.04.4, if using the HWE stack, your system kernel will upgrade to the kernel found in Ubuntu 21.10 (currently impish and not released; 5.13 currently, but we’ve not reached kernel freeze yet so it may change; again 20.04.4 will be released a few months after 21.10 has been released.

At 20.04.5, if using the HWE stack, your system upgrades for the last time to the GA stack of the next LTS, ie. 22.04, again the release is a few months after 22.04 has been released.

Users of 20.04 with the GA stack upgrade through 20.04 to 20.04.5 too, but their kernel always remains on the stable 5.4 kernel; they don’t get access to later kernel modules (drivers) offered by later stacks.

FYI: If you want to see the release schedule for focal fossa you can see it here ; this is written purely from memory.

For details about the GA/HWE stack choices - I’ll refer you to the wiki. The stack you’re using can be changed post-install, and you can have both stacks installed (ie. I find useful for problem solving on occasion). You’ll also find some 3rd party software is only generated for the GA stack.

FYI: The LXQt that came with 20.04 used the LTS Qt5 stack (Qt 5.12.8), so LTS releases may not be the latest LXQt at release time, but will be the version that aligns with the latest LTS Qt5 stack available for security reasons.

Yes I’ve seen your requests for help with color but I have no answers there, so I’ve stuck to answering the generic Ubuntu questions [in this reply].


Thanks for your help.
Perhaps you understand because I wait test 20.04.3 if has the same white color issue.
I not see any information about it or how fix it. Trying changing bright , contrast or gamma value not fix. Is how if is anything between user color settings and video output that even xrandr not may change that issue.

Even with your reply I still not understand … one of the main detail is that Ubuntu LTS releases have to kernel stack choices and current hirsute not was does it ?
Another detail is LTS not has ISO software updated and current hirsute will use release date software updated ?

You say
“At 20.04.3, if using the HWE stack, your system kernel upgraded to the 5.11 kernel, which was the kernel stack from 21.04 (again 21.04 released months before 20.04.3)”
is about upgrade. If installing using a 20.04.3 ISO the OS installed will use 5.11 ?

In moment trying figure any solution about white color and xscreensaver not working correctly.
Perhaps the solution is wait Lubuntu use wayland.
Downloading 20.04.3 for testing.

Lubuntu 20.04.3 LTS media will use the kernel stack from 21.04; ie. 5.11 kernel.

Lubuntu 20.04 LTS & Lubuntu 20.04.1 LTS media only used the GA stack, ie. the initial stack provided with 20.04, which was the 5.4 kernel. Installs from these ISOs will remain on the GA stack, ie. remain on the 5.4 kernel.

Lubuntu 20.04.2 & later media default to HWE with upgraded stacks from non-LTS releases; 20.04.2 used the stack from 20.10, 20.04.3 uses the stack from 21.04 etc… The media itself tells you the stack you have at install time, but they’ll all upgrade to the latest stack (which currently is 5.11 or the 21.04 stack).

You can boot 20.04.2 media, or Lubuntu 20.10 media to try the 5.8 stack; but please note it will upgrade post-install to be the 5.11 stack (as used by 21.04).

Kernel modules, or more commonly known as drivers are related to the kernel; thus kernel stack matters.

I will test 20.04.3 and if not has problem in white color I will spread that solution to another users.
20.04.3 ISO not has softwares updated thus how 21.04 does (Libreoffice 7.2) ?

I provide the release notes for 20.04.3 in a prior comment.

If you want specifics as to what gets included; you can always look at the manifest which is available at the same location where you download the ISO.

It’s Lubuntu 20.04 LTS with a newer kernel stack (that from 21.04) and security patches & fixes applied. Security fixes are back-ported to the version of software that originally came out with 20.04, except in rare circumstances where the backport is more work than providing a new package along with all the testing involved (if you want an example, see this link relating to thunderbird in 20.04).

20.04.3 not has updates for all components.
thanks for your reply.

thanks for the awesome information.

1 Like

This topic was automatically closed 30 days after the last reply. New replies are no longer allowed.