I have two questions:

1. I currently work for company A and would like to apply for a H-1B visa transfer to work for company B. I am Canadian and have gone back and forth between the US and Canada on vacation since receiving my H-1B and never went to the consulate to receive the visa stamp in my passport. I noticed that I am supposed to provide a copy of my visa when applying for the visa transfer to company B. But I don't have one since it wasn't needed to travel to and from Canada. Can I still apply for the visa transfer if I don't have a visa stamp from the consulate in my passport? If yes, will it be a problem if they know I have been in Canada since receiving the visa?

2. I have a trip planned to Europe next month. As a Canadian on H-1B, do I need a visa stamp to get back into the US from Europe? Or do Canadians not need a visa stamp for any type of travel? Will I have to go to Canada before I go to Europe to first get the stamp?

Thank you!