Well, in general, it was fixed. I mean — if some configuration is not changed, shortcuts will be not recreated and so, pinned icon remains. In your case, it seems, shortcut related configuration detected as changed and it leads to icon reregistration. Please provide your NSIS config.

The problem is the pinned icon is being removed from the task bar. The icon appears on the desktop again...but it's just removed from the bottom bar in windows.

"nsis": {
      "oneClick": false,
      "perMachine": true,
      "allowElevation": true,
      "allowToChangeInstallationDirectory": true,
      "runAfterFinish": false,
      "include": "build/badlion.nsh",
      "unicode": true,
      "differentialPackage": true
    },

Just for further clarification @develar in case something wasn't clear with the way windows words things:

Before Upgrading to 1.1:

After Upgrading from 1.0 to 1.1:

In the first part of the upgrade it seems to remove the existing icon from the task bar.

Reproduced.

Any chance of getting this resolved soonish @develar? If not can you point me to where you think the issue is happening so I can try to take a crack at it. Don't have an environment at the moment but I will in a few days.

allowToChangeInstallationDirectory: true
Looking at the code, it looks like when enabling this setting, keepShortcuts bool is automatically set to false.

I don't think this is not how it should be working, if the installation path, app args etc didn't change between old and new shortcut, it shouldn't recreate it. It's just missing a shortcut "content" check around here.

(might need to check other installers for similar mistakes ?)
(I have no knowledge about NSIS, i don't know how to make these changes myself)

The Bug is also in Latest(Version 20.19.x)

This bug is still present.