Steps to reproduce:

• Install an older version of a macro, like Mathjax 1.1.4
• As an admin, search for "mathjax" in the macro dialog

Expected result:

Mathjax is only listed as a regular macro to be inserted

Actual result:

Mathjax is both listed as installed and as not installed:

The same happens in the quick actions:

Though even worse, in the quick actions:

• the install action is listed before the installed macro
• clicking on the installed macro triggers the install action

Surprisingly, when cancelling the installation, the macro is still inserted.

Note that this also happens when the macro is installed as a dependency (e.g., of the "Pro Macros") and the macro thus isn't listed as upgrade in the extension manager.