As I know, it's impossible.

I suppose you meant "update Deepin with latest software packages", not "update Deepin v15 to v20".

The "update" function in the Control Center will try to update all packages as it could. If you'd like to keep some applications in their older version, you can use the APT command:

Replace "firefox" with the name of the application you'd like to hold.
Please note: some applications requires up-to-date system libraries, so if you hold these applications, some part of the system will also be held.

Do not try this.

there is not a clear boundary between system and software in package manager.you may try flatpak,snap or appimage instead.

I mean for example update to Deepin 20, but keep Vmware 14, or Virtualbox 6.0, ignoring such things like Virtualbox 6.1

Yea I noticed that the OS, and programs are often tied together. It's not like Windows, where I can run firefox 38 on Windows 10. So if I like using old programs, is it recomended to use the old OS. I am on Deepin 15.9.

Thanks

你说的这些不是系统自带的，不会升级吧

Edited by dziban at 2020-5-6 07:17

you could still run older versions of programs, but they would have to be appimages, snaps, flatpacks and such, they are sandboxed versions of the apps that can run on any distro regardless of dependencies, cause they have all what they need to run in them thus making them distro agnostic.

Edited by dziban at 2020-5-6 07:23

try using appimages of those programs instead of the ones found on the deepin store, you could save them all in your /home partition(if you have one) and when you upgrade or if you decide to hope to another distro, they will be there. you can add them to your app launcher by making a custom .desktop file for them. some appimages ask you to do that automatically for you when you execute them for the first time.

To make the .desktop file creation process easier I've made an addon for deepin v20, not sure if it works on 15.11. you can find it here :

https://github.com/Dziban-dev/dde-appknitter