Walmart Price Per Unit

What's new:
+ Allow user to select preferred unit for liquid and weighted products
+ Improve background process. Now the extension only run when page is ready

Descriptions:
+ This extension works on walmart.ca search result page, extracts the item price and unit (like "12 ct"), and displays the price per unit directly under each product.
+ Search for a grocery items like "eggs" or "milk" to see the price per unit for each product.
+ For liquid products like milk, the unit will be 100 ml, or 1 oz
+ For weighted products like meat, the unit will be 100 g, or 1 lb