There are 2 words "handing" & "fails us" I didn't understand what it means
Here is the context:
"Here’s the screen you’ll see after you add your item to the cart. They have a very handing ‘image cart’ which lets you see what you put in it. To remove an item, click the link in blue text on the same row. From here on out auto-translate fails us and there is no more English; bear with me…"
Please someone help me???It's just a part of the guide "how to order from Rakuten Shops"

Question

There are 2 words "handing" & "fails us" I didn't understand what it means
Here is the context: 
"Here’s the screen you’ll see after you add your item to the cart. They have a very handing ‘image cart’ which lets you see what you put in it. To remove an item, click the link in blue text on the same row. From here on out auto-translate fails us and there is no more English; bear with me…"
Please someone help me???It's just a part of the guide "how to order from Rakuten Shops"

Answer

"handing" is an error and should probably be "handy" = useful
"fails us" means that the automatic translation software stops giving any useful translations so there is no more English I can provide

Answer

I think "handing 'image cart'"  must be a mistake. ... a very handy cart image" would make sense to me. Handy means close by and easy to use. Cart image would be a little photo of a shopping cart/trolley.

"Auto translate fails us". 'Auto translate' is the subject. 'Fails' is the verb and it means to not complete a task. So the program automatically translating has not finished the job.

If I could see the real website, I might be able to offer more insight.

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