Which GNOME shell extensions directory takes precedence/priority?

Question

According to this answer, GNOME shell extensions can be found in two directories. Namely,

• ~/.local/share/gnome-shell/extensions/
• /usr/share/gnome-shell/extensions/

If I have the same extension (but of different versions) installed into each of these directories, how do I know which extension will actually be used when I log in as a standard user? Or will such a situation cause a conflict to GNOME shell? The assumption here is that this extension is enabled.

E.g.

• ~/.local/share/gnome-shell/extensions/extA@gmail.com
• /usr/share/gnome-shell/extensions/extA@gmail.com

Also, as root/sudo this command was executed.

$ gsettings set org.gnome.shell enabled-extensions "['extA@gmail.com']"

Now, when I am logged-in as user, which extensions will I be using?

Answer 1

Like many other things (for example .desktop launchers for applications), the local directory has the higher priority.

(Now defunct) 'Ubuntu GNOME' flavour of Ubuntu used to come with a few extensions (e.g. AlternateTab, Applications Menu, Window List etc.) installed system-wide (hence in the /usr/share/gnome-shell/extensions/ directory) by default. If there was an update for such an extension and if the user updated it using the GNOME Shell Extensions website, it used to create a local copy (in the ~/.local/share/gnome-shell/extensions/ directory) of the extension with the updated version overriding the older system-wide one.