I'm trying to modify an Administrative Zimlet. Since now I've tried to modify files in /opt/zimbra/zimlets-deployed/com_zimbra_zimlet files and works (after a zmprov fc zimlet and other stuff...).
Now I've read that is simpler to develop a zimlet in /opt/zimbra/zimlets-deployed/_dev directory, cause here you have not to deploy it or flush any cache.
So I've undeployed my Zimlet and I've created the _dev dir in this manner
# mkdir /opt/zimbra/zimlets-deployed/_dev
# unzip com_zimbra_zimlet.zip -d /opt/zimbra/zimlets-deployed/_dev/com_zimbra_zimlet
# chown -R zimbra:zimbra /opt/zimbra/zimlets-deployed/_dev
... but I can't see my Zimlet.

Tried with ?dev=1 too, but no success: my Zimlets JS files are not loaded by the browser.

Am I missing something?

Any help would be appreciated.