1. Open invoice creation form
2. Click 'Generate from template'
3. Click 'Create' in Products and services attribute
4. Fill in 'Quantity'
5. Fill in all requered fileds
6. Remove value of 'Quantity'
Actual result: validation message is missing
Expected result: validation message is presented

7. Click 'Submit' button
Actual result: 'Quantity' is filled in