Hi community, SOS! In the PoS view, when clicking on products, it returns the error message:

Uncaught TypeError: Cannot read property 'add_product' of null

http://*.*.*.*/web/content/623-50459db/point_of_sale.assets.js:325

Traceback:

TypeError: Cannot read property 'add_product' of null

at OdooClass.ScreenWidget.extend.click_product (http://*.*.*.*/web/content/623-50459db/point_of_sale.assets.js:325:256)

at Object.product_list_widget.ProductListWidget.click_product_action (http://*.*.*.*/web/content/623-50459db/point_of_sale.assets.js:324:951)

at HTMLSpanElement.click_product_handler (http://*.*.*.*/web/content/623-50459db/point_of_sale.assets.js:321:1738)

While if switch to the debug mode, everything works perfectly. Your guidance is appreciated. 

Version: Odoo 9, recently installed from Github source

Server: Ubuntu 14.04

Cheers,

August