Why can’t I add the Recycle Bin to a Portal?

The Recycle Bin is a special icon type, it is not a normal file/folder, so it cannot be moved to a portal.

Thanks to GitHub user wstanzl, here is a workaround:
You can add an equivalent to recycle bin to your portal like this:

1. On your standard desktop, create a new shortcut
2. Fill in the Location as
   C:\Windows\explorer.exe shell:RecycleBinFolder
3. Name it “Recycle Bin”
4. To give it the Recycle Bin icon, right click the new shortcut, choose Change Icon,
   replace the file name “C:\Windows\explorer.exe” with
   “%SystemRoot%\System32\shell32.dll” -> you will find a Recycle Bin Icon there.
5. Drag the shortcut onto your portal.

Source: https://github.com/Ross-Patterson/Portals-Desktop-Organization/issues/251#issuecomment-2077922208