Created theme's customizer doesn't work

[luigidsoftware]

I've created many themes with your _strap and everything always went good. But today I'm facing a problem that I cannot solve. I've installed wordpress in localhost, as always, and then the _strap theme. I created the theme, then began to customize it. I added some settings and controls to it, that show in customizer, but when I go to save them, the db doesn't keep changes. I've noticed that even default settings of customizer are not saved.
If I switch theme to Twenty Seventeen everything goes right. If I switch back to my theme, error. With wp_debug on, the customizer doesn't work at all and browser console says: "Uncaught SyntaxError: Unexpected token <" at http://www.bricko.it/wp-admin/customize.php?theme=bricko&return=http%3A%2F%2Fwww.bricko.it%2Fwp-admin%2Fthemes.php

I really don't know what's the problem.

[ptbello]

Hi Luigi, I can't reproduce the issue locally.
Please attach a zip with your newly created theme that causes an error in the customizer.