Please post a link to an example on your site.

For a quick test, please set the Swipe option in the MediaBox parameters to No, then relaod the page and try the MediaBox and menu items again.

Any change?

From testing and debugging, this doesn’t appear to be caused by JCE MediaBox itself. The click on the Gantry menu is reaching the menu correctly, but the Gantry menu script is cancelling the action after the Mediabox is closed.

It looks like Gantry is treating the click after closing the popup as if it were part of its own page interaction handling, and as a result the first menu click is ignored.

Could you please check that you are running the latest version of the Gantry framework?

If possible, you could also try temporarily disabling MediaBox just to confirm the behaviour changes, this helps narrow it down further.

You don't think it's odd that opening the modal and dismissing it a second time clears the issue?

What it suggests is that Gantry’s menu script is ending up in an “in-between” state after the first Mediabox interaction. When the Mediabox is opened and closed again, that state gets reset, which is why the menu starts working normally again.

From debugging, the click event itself is not being blocked by MediaBox. The Gantry menu script is receiving the click and then cancelling it internally. The first open/close sequence appears to leave Gantry’s menu logic thinking it shouldn’t react to the next click. The second open/close clears that condition.

Please try JCE MediaBox 2.2.4 Beta - https://www.joomlacontenteditor.net/downloads/mediabox/development

Clear you browser cache after install.